結果
| 問題 | No.225 文字列変更(medium) |
| ユーザー |
 ysuzuki5321
|
| 提出日時 | 2020-03-11 10:22:58 |
| 言語 | C++14 (gcc 12.3.0 + boost 1.83.0) |
| 結果 |
AC
|
| 実行時間 | 9 ms / 5,000 ms |
| コード長 | 19,537 bytes |
| コンパイル時間 | 1,969 ms |
| コンパイル使用メモリ | 144,628 KB |
| 実行使用メモリ | 11,520 KB |
| 最終ジャッジ日時 | 2024-11-16 00:04:38 |
| 合計ジャッジ時間 | 3,104 ms |
|
ジャッジサーバーID （参考情報） |
judge1 / judge4 |
（要ログイン）
テストケース
テストケース表示| 入力 | 結果 | 実行時間 実行使用メモリ |
|---|---|---|
| testcase_00 | AC | 7 ms
11,392 KB |
| testcase_01 | AC | 8 ms
11,392 KB |
| testcase_02 | AC | 5 ms
11,392 KB |
| testcase_03 | AC | 6 ms
11,264 KB |
| testcase_04 | AC | 6 ms
11,392 KB |
| testcase_05 | AC | 6 ms
11,392 KB |
| testcase_06 | AC | 6 ms
11,520 KB |
| testcase_07 | AC | 6 ms
11,264 KB |
| testcase_08 | AC | 6 ms
11,520 KB |
| testcase_09 | AC | 6 ms
11,264 KB |
| testcase_10 | AC | 6 ms
11,392 KB |
| testcase_11 | AC | 6 ms
11,264 KB |
| testcase_12 | AC | 9 ms
11,392 KB |
| testcase_13 | AC | 8 ms
11,392 KB |
| testcase_14 | AC | 8 ms
11,392 KB |
| testcase_15 | AC | 9 ms
11,264 KB |
| testcase_16 | AC | 8 ms
11,520 KB |
| testcase_17 | AC | 8 ms
11,264 KB |
| testcase_18 | AC | 8 ms
11,264 KB |
| testcase_19 | AC | 9 ms
11,392 KB |
| testcase_20 | AC | 8 ms
11,392 KB |
| testcase_21 | AC | 8 ms
11,392 KB |
ソースコード
#include <stdio.h>
#include <sstream>
#include <iostream>
#include <fstream>
#include <string.h>
#include <vector>
#include <map>
#include <algorithm>
#include <utility>
#include <set>
#include <cctype>
#include <queue>
#include <stack>
#include <cstdio>
#include <cstdlib>
#include <cmath>
#include <deque>
#include <limits>
#include <iomanip>
#include <ctype.h>
#include <unordered_map>
#include <random>
#include <bitset>
#define _USE_MATH_DEFINES
#include <iostream>
#include <math.h>
#include <complex>
using namespace std;
typedef long long ll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
typedef pair<ll, double> pld;
typedef pair<double, double> pdd;
typedef pair<double, ll> pdl;
typedef pair<int, char> pic;
typedef vector<ll> vl;
typedef vector<int> vi;
typedef priority_queue<ll, vector<ll>, greater<ll>> llgreaterq;
typedef priority_queue<pll, vector<pll>, greater<pll>> pllgreaterq;
typedef priority_queue<pair<ll, pll>, vector<pair<ll, pll>>, greater<pair<ll, pll>>> plpllgreaterq;
typedef priority_queue<vi, vector<vi>, greater<vi>> vigreaterq;
typedef priority_queue<vl, vector<vl>, greater<vl >> vlgreaterq;
#define bit(x,v) ((ll)x << v)
#define rep(x,v) for(int x=0;x<v;x++)
#define rep2(x,f,v) for(int x=f;x<v;x++)
// 許容する誤差ε
#define EPS (1e-10)
// 2つのスカラーが等しいかどうか
#define EQ(a,b) (abs((a)-(b)) < EPS)
// 2つのベクトルが等しいかどうか
#define EQV(a,b) ( EQ((a).real(), (b).real()) && EQ((a).imag(), (b).imag()) )
#define all(a) a.begin(),a.end()
#define all0(a) memset(a,0,sizeof(a))
const ll INF = 1000000007;
const int MAX = 2000010;
const int MOD = 1000000007;
long long fac[MAX], finv[MAX], inv[MAX];
void COMinit() {
fac[0] = fac[1] = 1;
finv[0] = finv[1] = 1;
inv[1] = 1;
for (int i = 2; i < MAX; i++) {
fac[i] = fac[i - 1] * i % MOD;
inv[i] = MOD - inv[MOD % i] * (MOD / i) % MOD;
finv[i] = finv[i - 1] * inv[i] % MOD;
}
}
// 二項係数計算
long long COM(int n, int k) {
if (n < k) return 0;
if (n < 0 || k < 0) return 0;
return fac[n] * (finv[k] * finv[n - k] % MOD) % MOD;
}
ll gcd(ll a, ll b) {
if (b == 0) return a;
return gcd(b, a % b);
}
int pr[200010];
int lank[200010];
void uini(int n) {
for (size_t i = 0; i <= n; i++)
{
pr[i] = i;
}
}
int parent(int x) {
if (x == pr[x]) return x;
return pr[x] = parent(pr[x]);
}
int same(int x, int y) {
return parent(x) == parent(y);
}
bool unit(int x, int y) {
int px = parent(x);
int py = parent(y);
if (px == py) return false;
if (lank[px] < lank[py]) {
pr[py] = px;
lank[px] += lank[py] + 1;
}
else {
pr[px] = py;
lank[py] += lank[px] + 1;
}
return true;
}
ll bit[200010];
int max_n = 200000;
int pm = 0;
void add(int x) {
while (max_n >= x)
{
bit[x]++;
x += x & -x;
}
}
void sub(int x) {
while (max_n >= x)
{
bit[x]--;
x += x & -x;
}
}
ll merge(ll* a, int left, int mid, int right) {
ll n1 = mid - left;
ll n2 = right - mid;
vector<int> L(n1 + 1);
vector<int> R(n2 + 1);
for (size_t i = 0; i < n1; i++)
{
L[i] = a[left + i];
}
for (size_t i = 0; i < n2; i++)
{
R[i] = a[mid + i];
}
L[n1] = INF;
R[n2] = INF;
ll i = 0;
ll j = 0;
ll r = 0;
for (size_t k = left; k < right; k++)
{
if (L[i] <= R[j]) {
a[k] = L[i];
i++;
}
else {
a[k] = R[j];
r += n1 - i;
j++;
}
}
return r;
}
ll merge2(pair<int, char>* a, int left, int mid, int right) {
ll n1 = mid - left;
ll n2 = right - mid;
vector<pair<int, char>> L(n1 + 1);
vector<pair<int, char>> R(n2 + 1);
for (size_t i = 0; i < n1; i++)
{
L[i] = a[left + i];
}
for (size_t i = 0; i < n2; i++)
{
R[i] = a[mid + i];
}
L[n1] = make_pair(INF, ' ');
R[n2] = make_pair(INF, ' ');
ll i = 0;
ll j = 0;
ll r = 0;
for (size_t k = left; k < right; k++)
{
if (L[i].first <= R[j].first) {
a[k] = L[i];
i++;
}
else {
a[k] = R[j];
r += n1 - i;
j++;
}
}
return r;
}
ll mergeSort2(pair<int, char>* a, int left, int right) {
ll res = 0;
if (left + 1 < right) {
int mid = (left + right) / 2;
res = mergeSort2(a, left, mid);
res += mergeSort2(a, mid, right);
res += merge2(a, left, mid, right);
}
return res;
}
ll mergeSort(ll* a, int left, int right) {
ll res = 0;
if (left + 1 < right) {
int mid = (left + right) / 2;
res = mergeSort(a, left, mid);
res += mergeSort(a, mid, right);
res += merge(a, left, mid, right);
}
return res;
}
int partition(pair<int, char>* a, int p, int r) {
pair<int, char> x = a[r];
int i = p - 1;
for (size_t j = p; j < r; j++)
{
if (a[j].first <= x.first) {
i++;
swap(a[i], a[j]);
}
}
swap(a[i + 1], a[r]);
return i + 1;
}
void quick(pair<int, char>* a, int p, int r) {
if (p < r) {
int q = partition(a, p, r);
quick(a, p, q - 1);
quick(a, q + 1, r);
}
}
ll n;
int ci = 0;
ll P[1000010];
struct Node {
int key;
int priority;
Node* parent, * left, * right;
Node(int key, int priority);
Node() {}
};
Node NIL;
Node::Node(int key, int priority) : key(key), priority(priority) {
left = &NIL;
right = &NIL;
}
Node* root = new Node();
void cenrec(Node* k) {
if (k->key == NIL.key) return;
cenrec(k->left);
cout << " " << k->key;
cenrec(k->right);
}
void fastrec(Node* k)
{
if (k->key == NIL.key) return;
cout << " " << k->key;
fastrec(k->left);
fastrec(k->right);
}
void insert(Node* v) {
Node* y = &NIL;
Node* x = root;
while (x->key != NIL.key)
{
y = x;
if (v->key < x->key) {
x = x->left;
}
else {
x = x->right;
}
}
v->parent = y;
if (y->key == NIL.key) {
root = v;
}
else if (v->key < y->key) {
y->left = v;
}
else {
y->right = v;
}
}
Node* find(Node* k, ll v)
{
if (k->key == NIL.key) return &NIL;
if (k->key == v) return k;
if (v < k->key) return find(k->left, v);
return find(k->right, v);
}
void delp12(Node* x) {
if (x->key == NIL.key) return;
Node* l = x->left;
Node* r = x->right;
Node* pr = x->parent;
if (l->key == NIL.key
&& r->key == NIL.key) {
if (pr->left == x) {
pr->left = &NIL;
}
else pr->right = &NIL;
}
else if (l->key != NIL.key) {
if (pr->left == x) {
pr->left = l;
}
else pr->right = l;
l->parent = pr;
}
else if (r->key != NIL.key) {
if (pr->left == x) {
pr->left = r;
}
else pr->right = r;
r->parent = pr;
}
}
Node* get_next(Node* k) {
if (k->key == NIL.key) return &NIL;
Node* res = get_next(k->left);
if (res->key != NIL.key) return res;
return k;
}
void del(Node* x) {
if (x->key == NIL.key) return;
Node* l = x->left;
Node* r = x->right;
Node* pr = x->parent;
if (l->key != NIL.key && r->key != NIL.key) {
Node* nex = get_next(r);
x->key = nex->key;
delp12(nex);
}
else {
delp12(x);
}
}
Node* rightRotate(Node* t) {
Node* s = t->left;
t->left = s->right;
s->right = t;
return s;
}
Node* leftRotate(Node* t) {
Node* s = t->right;
t->right = s->left;
s->left = t;
return s;
}
Node* _insert(Node* t, int key, int priority) {
if (t->key == NIL.key) {
return new Node(key, priority);
}
if (key == t->key) {
return t;
}
if (key < t->key) {
t->left = _insert(t->left, key, priority);
if (t->priority < t->left->priority) {
t = rightRotate(t);
}
}
else {
t->right = _insert(t->right, key, priority);
if (t->priority < t->right->priority) {
t = leftRotate(t);
}
}
return t;
}
Node* delete1(Node* t, int key);
Node* _delete(Node* t, int key) {
if (t->left->key == NIL.key && t->right->key == NIL.key) {
return &NIL;
}
else if (t->left->key == NIL.key) {
t = leftRotate(t);
}
else if (t->right->key == NIL.key) {
t = rightRotate(t);
}
else
{
if (t->left->priority > t->right->priority) {
t = rightRotate(t);
}
else
t = leftRotate(t);
}
return delete1(t, key);
}
Node* delete1(Node* t, int key) {
if (t->key == NIL.key) {
return &NIL;
}
if (key < t->key) {
t->left = delete1(t->left, key);
}
else if (key > t->key) {
t->right = delete1(t->right, key);
}
else return _delete(t, key);
return t;
}
int H;
int left(int i) {
return i * 2 + 1;
}
int right(int i) {
return i * 2 + 2;
}
ll heap[2000010];
void maxHeapify(int i) {
int l = left(i);
int r = right(i);
int largest = 0;
if (l < H && heap[l] > heap[i])
largest = l;
else
largest = i;
if (r < H && heap[r] > heap[largest])
largest = r;
if (largest != i) {
swap(heap[i], heap[largest]);
maxHeapify(largest);
}
}
int pare(int i) {
return (i - 1) / 2;
}
void raise(int i) {
int l = pare(i);
if (l < 0) return;
if (heap[l] < heap[i]) {
swap(heap[i], heap[l]);
raise(l);
}
}
void minHeapify(int i) {
int l = left(i);
int r = right(i);
int minimam = 0;
if (l < H && heap[l] < heap[i])
minimam = l;
else
minimam = i;
if (r < H && heap[r] < heap[minimam])
minimam = r;
if (minimam != i) {
swap(heap[i], heap[minimam]);
minHeapify(minimam);
}
}
void buildMaxHeap() {
for (int i = H / 2; i >= 0; i--)
{
maxHeapify(i);
}
}
int dx[] = { -1,0,1,0 };
int dy[] = { 0,-1,0,1 };
std::vector<int> find_all(const std::string str, const std::string subStr) {
std::vector<int> result;
int subStrSize = subStr.size();
int pos = str.find(subStr);
while (pos != std::string::npos) {
result.push_back(pos);
pos = str.find(subStr, pos + 1);
}
return result;
}
//ll memo[100010];
//ll next[100010];
//ll dm[100010];
//int f[100010];
//ll rec(int x) {
//
// if (~memo[x]) return memo[x];
// if (x == n) {
// dm[n] = 1;
// return 1;
// }
// ll *res = &memo[x];
// *res = 0;
// set<int> st;
// st.insert(f[x]);
// for (int i = x + 1; i <= n; i++)
// {
// if (~memo[i]) {
// *res += memo[i] + 1;
// *res %= INF;
// break;
// }
//
// *res += rec(i);
// *res %= INF;
// if (st.find(f[i]) != st.end()) {break; }
// st.insert(f[i]);
// }
//
// return *res;
//}
#define bit(x,v) ((ll)x << v)
class BIT {
static const int MAX_N = 1000010;
public:
BIT() { memset(bit, 0, sizeof(bit)); }
int bit[MAX_N + 1], n;
int sum(int i) {
int s = 0;
while (i > 0)
{
s += bit[i];
i -= i & -i;
}
return s;
}
void add(int i, int x) {
while (i <= n)
{
bit[i] += x;
i += i & -i;
}
}
void clear() {
memset(bit, 0, sizeof(bit));
}
int a[MAX_N];
void bable_swap_count() {
ll ans = 0;
for (size_t j = 0; j < n; j++)
{
ans += j - sum(a[j]);
add(a[j], 1);
}
printf("%lld\n", ans);
}
int search(int s, int x) {
ll half = (s + x) / 2;
ll sh = sum(x);
ll sl = sum(half);
ll st = sum(s);
if (sh - sl == 0) {
return x;
}
if (sh - sl < x - half) {
return search(half, x);
}
if (sl - st == 0) {
return half;
}
if (sl - st < half - s) {
return search(s, half);
}
return -1;
}
int lankSearch(int lank) {
return lankSearch(lank, 0, MAX_N);
}
int lankSearch(int lank, int s, int t) {
ll half = (s + t) / 2;
ll v = sum(half);
ll v1 = sum(t);
ll v2 = sum(s);
if (lank == 1) {
if (s + 1 >= t) return t;
else if (v - v2 > 0) {
return lankSearch(lank, s, half);
}
else return lankSearch(lank, half, t);
}
if ((v - v2) < lank) {
return lankSearch(lank - (v - v2), half, t);
}
if ((v - v2) >= lank) {
return lankSearch(lank, s, half);
}
return -1;
}
};
class BIT2 {
static const int MAX_N = 1000010;
public:
BIT2() { memset(bit, 0, sizeof(bit)); }
ll bit[MAX_N + 1], n;
ll gmax(int i) {
ll s = 0;
while (i > 0)
{
s = max(bit[i], s);
i -= i & -i;
}
return s;
}
void add(int i, ll x) {
while (i <= n)
{
bit[i] = max(bit[i], x);
i += i & -i;
}
}
void clear() {
memset(bit, 0, sizeof(bit));
}
};
vector<ll> getp(ll n) {
vector<ll> res;
ll a = 2;
if (n % 2 == 0) {
res.push_back(2);
while (n % 2 == 0)n /= 2;
}
for (ll i = 3; i * i <= n; i += 2)
{
if (n % i == 0) {
res.push_back(i);
while (n % i == 0)n /= i;
}
}
if (n != 1) res.push_back(n);
return res;
}
vector<ll> getp2(ll n) {
vector<ll> res;
ll a = 2;
if (n % 2 == 0) {
while (n % 2 == 0) { n /= 2; res.push_back(2); }
}
for (ll i = 3; i * i <= n; i += 2)
{
if (n % i == 0) {
while (n % i == 0) { n /= i; res.push_back(i); }
}
}
if (n != 1) res.push_back(n);
return res;
}
vector<pll> getp3(ll n) {
vector<pll> res;
ll a = 2;
int cnt = 0;
if (n % 2 == 0) {
res.push_back(make_pair(2, 0));
while (n % 2 == 0) { n /= 2; res[cnt].second++; }
cnt++;
}
for (ll i = 3; i * i <= n; i += 2)
{
if (n % i == 0) {
res.push_back(make_pair(n, 0));
while (n % i == 0) { n /= i; res[cnt].second++; }
cnt++;
}
}
if (n != 1) res.push_back(make_pair(n, 1));
return res;
}
vector<ll> getDivisors(ll n) {
vector<ll> res;
ll a = 2;
res.push_back(1);
for (ll i = 2; i * i <= n; i++)
{
if (n % i == 0) {
res.push_back(i);
if (n / i != i)
res.push_back(n / i);
}
}
return res;
}
struct ve {
public:
vector<ve> child;
int _t = INF;
ve(int t) :_t(t) {}
ve(ve _left, ve _right) {
_t = _left._t + _right._t;
child.push_back(_left);
child.push_back(_right);
}
bool operator<(const ve& t) const {
return _t > t._t;
}
};
vector<bool> elas(ll n) {
vector<bool> r(n);
for (ll i = 3; i < n; i += 2)
{
r[i] = 1;
}
r[0] = 0;
r[1] = 0;
r[2] = 1;
for (ll i = 3; i * i < n; i += 2)
{
if (!r[i]) continue;
ll ti = i * 2;
while (ti < n)
{
r[ti] = false;
ti += i;
}
}
return r;
}
bool isprime(ll v) {
for (ll i = 2; i * i <= v; i++)
{
if (v % i == 0) return false;
}
return true;
}
ll lcm(vector<ll> v) {
if (v.size() == 0) return 0;
ll t = v[0];
for (size_t i = 1; i < v.size(); i++)
{
t = v[i] * t / gcd(v[i], t);
}
return t;
}
ll eulerphi(ll n) {
auto p = getp(n);
double u = n;
for (auto v : p) {
u *= (double)(v - 1) / (double)v;
}
return u;
}
double revs(double x) {
ll dig = 0;
stringstream st;
st << std::fixed << setprecision(0) << x;
string v = st.str();
reverse(v.begin(), v.end());
return stod(v);
}
bool chkparindrome(double x) {
stringstream st;
st << std::fixed << setprecision(0) << x;
string p = st.str();
for (size_t i = 0; i < p.size() / 2; i++)
{
if (p[i] != p[p.size() - i - 1]) {
return false;
}
}
return true;
}
ll digitC(double x) {
stringstream st;
st << fixed << setprecision(0) << x;
return st.str().size();
}
ll digitSum(double x) {
stringstream st;
st << std::fixed << x;
string p = st.str();
ll rs = 0;
for (size_t i = 0; i < p.size(); i++)
{
if (p[i] == '.') break;
rs += p[i] - '0';
}
return rs;
}
pdd recs(int x) {
if (x == 0) return make_pair(1, 2);
pdd d = recs(x - 1);
auto nu = d.second * 2.0 + d.first;
auto de = d.second;
return make_pair(de, nu);
}
ll caldig(ll a) {
ll r = 0;
while (a > 0) { a /= 10; r++; }
return r;
}
int chav(char v) {
if (v <= 'Z') return v - 'A';
return v - 'a' + 26;
}
char itoch(int i) {
if (i < 26) return i + 'A';
return (i - 26) + 'a';
}
int crmp[1000][1000];
int countR(ll base, ll x, ll y, int deep) {
if (~crmp[x][y]) {
return deep - crmp[x][y];
}
crmp[x][y] = deep;
double nu = sqrt(base) + x;
double de = (base - (x * x)) / y;
ll u = nu / de;
ll nx = x - (u * de);
return countR(base, -nx, de, deep + 1);
}
bool isPermutation(ll x, ll y) {
int c1[10];
int c2[10];
memset(c1, 0, sizeof(c1));
memset(c2, 0, sizeof(c2));
while (x > 0)
{
c1[x % 10]++;
x /= 10;
}
while (y > 0)
{
c2[y % 10]++;
y /= 10;
}
for (size_t i = 0; i < 10; i++)
{
if (c1[i] != c2[i]) return false;
}
return true;
}
double heron(ll a, ll b, ll c) {
double s = (double)(a + b + c) / 2.0;
return sqrt(s * (s - a) * (s - b) * (s - c));
}
double calcThreePS(double x1, double y1, double x2, double y2, double x3, double y3) {
return abs((x1 * y2 + x2 * y3 + x3 * y1 - y1 * x2 - y2 * x3 - y3 * x1) / 2.0);
}
typedef vector<vl> mat;
class Matrix1 {
public:
static const int M = INF;
int n;
mat mul(mat& A, mat& B) {
mat C(A.size(), vl(B[0].size()));
for (size_t i = 0; i < A.size(); i++)
{
for (size_t k = 0; k < B.size(); k++)
{
for (size_t j = 0; j < B[0].size(); j++)
{
C[i][j] = (C[i][j] + A[i][k] * B[k][j]) % M;
}
}
}
return C;
}
mat pow(mat A, ll n) {
mat B(A.size(), vl(A.size()));
for (size_t i = 0; i < A.size(); i++)
{
B[i][i] = 1;
}
while (n > 0) {
if (n & 1) B = mul(B, A);
A = mul(A, A);
n >>= 1;
}
return B;
}
};
ll m;
ll stringDivRm(string s, ll k) {
ll v = 0;
for (size_t i = 0; i < s.size(); i++)
{
v *= 10;
v += s[i] - '0';
v %= k;
}
return v;
}
ll repPow(ll b, ll x,ll md) {
ll res = 1;
ll v = b;
while (x > 0)
{
if (x & 1) {
res *= v;
res %= md;
}
v *= v;
v %= md;
x >>= 1;
}
return res;
}
ll repPow(ll b, ll x) {
return repPow(b, x, INF);
}
ll uar[1000010];
ll upr(ll u, ll r) {
return (fac[u] * finv[u-r]) % INF;
}
ll partitionMemo[20010][110];
ll partitionNum(ll v, ll k) {
if (k == 1) return 1;
if (v <= 1) return 1;
if (~partitionMemo[v][k]) return partitionMemo[v][k];
ll r = 0;
if (v < k) {
r = partitionNum(v,v);
}
else
r = partitionNum(v, k - 1) + partitionNum(v - k, k);
r %= INF;
return partitionMemo[v][k] = r;
}
class SetTree1 {
public:
static const int MAX_N = 100000;
static const int MAX_Q = 100000;
int N, Q;
static const int DAT_SIZE = (1 << 18) - 1;
int A[MAX_N];
char T[MAX_Q];
ll data[DAT_SIZE];
void init(int _n) {
memset(data, 0, sizeof(data));
int p = 1;
while (p < _n)
{
p <<= 1;
}
N = p;
Q = N - 1;
}
void update(int a, int b) {
for (size_t i = a; i <= b; i++)
{
update(Q + i);
}
}
void update(int a) {
int x = data[a];
while (a > 0)
{
if (a % 2 == 0)a--;
a >>= 1;
data[a] += x;
}
}
void add(int a, int b, int x) {
add(a, b + 1, x, 0,0,N);
}
void add(int a, int b, int x, int k, int l, int r) {
if (a <= l && r <= b) {
data[k] += x;
}
else if (l < b && a < r) {
data[k] += (min(b, r) - max(a, l)) * x;
add(a, b, x, k * 2 + 1, l, (l + r) / 2);
add(a, b, x, k * 2 + 2, (l + r) / 2, r);
}
}
ll sum(int a, int b) {
return sum(a, b + 1, 0, 0, N);
}
ll sum(int a, int b, int k, int l, int r) {
if (b <= l || r <= a) return 0;
else if (a <= l && r <= b) {
return data[k];
}
else {
ll res = 0;
res += sum(a, b, k * 2 + 1, l, (l + r) / 2);
res += sum(a, b, k * 2 + 2, (l + r) / 2, r);
return res;
}
}
};
class Point {
public:
double x, y;
Point(double x = 0, double y = 0) :x(x), y(y) {}
Point operator + (Point p) { return Point(x + p.x, y + p.y); }
Point operator - (Point p) { return Point(x - p.x, y - p.y); }
Point operator * (double a) { return Point(a * x, a * y); }
Point operator / (double a) { return Point(x / a, y / a); }
double abs() { return sqrt(norm()); }
double norm() { return x * x + y * y; }
bool operator < (const Point& p)const {
return x != p.x ? x < p.x : y < p.y;
}
bool operator == (const Point& p) const {
return fabs(x - p.x) < EPS && fabs(y - p.y) < EPS;
}
static double dot(Point a, Point b) {
return a.x * b.x + a.y * b.y;
}
};
struct Segment {
Point p1, p2;
};
Point project(Segment s, Point p) {
Point base = s.p2 - s.p1;
double r = Point::dot(p - s.p1, base) / base.norm();
return s.p1 + base * r;
}
void solv() {
int m;
cin >> n >> m;
string s;
string t;
cin >> s;
cin >> t;
ll dp[1010][1010];
all0(dp);
for (size_t i = 0; i <= n; i++)
{
dp[i][0] = i;
}
for (size_t i = 0; i <= m; i++)
{
dp[0][i] = i;
}
for (size_t i = 1; i <= n; i++)
{
for (size_t j = 1; j <= m; j++)
{
int ad = s[i - 1] != t[j - 1];
dp[i][j] = min({ dp[i - 1][j] + 1,dp[i][j - 1] + 1,dp[i-1][j-1]+ad });
}
}
cout << dp[n][m] << endl;
}
int main() {
//COMinit();
solv();
return 0;
}