#define _CRT_SECURE_NO_WARNINGS #include "bits/stdc++.h" #if defined(_MSC_VER) || defined(ONLINE_JUDGE) #define getchar_unlocked _getchar_nolock #define putchar_unlocked _putchar_nolock #endif #define rep(i, n) for(int i=0; i<(n); ++i) #define FOR(i, m, n) for(int i=(m); i<(n); ++i) #define sz(x) ((int)(x).size()) #define all(x) (x).begin(),(x).end() #define rall(x) (x).rbegin(),(x).rend() #define mp make_pair #define pb push_back #define dump(x) cerr << #x << " = " << (x) << endl; using namespace std; using LL=long long; using VI=vector; using VL=vector; using VS=vector; using VD=vector; using VVI=vector; using VVL=vector; using PII=pair; using PLL=pair; const int inf = (int)1e9; const double pi = acos(-1.0); const LL MOD = 1000000007; const string Snum = "0123456789"; const int dx[] = { -1,0,1,0,-1,-1,1,1 }, dy[] = { 0,1,0,-1,-1,1,-1,1 }; templatevoid Sort(T& a) { sort(all(a)); } templatevoid RSort(T& a) { sort(rall(a)); } templatevoid Reverse(T& a) { reverse(all(a)); } templatevoid Unique(T& a) { a.erase(unique(all(a)), a.end()); } templateT Sorted(T a) { Sort(a); return a; } templateT RSorted(T a) { RSort(a); return a; } templateT Reversed(T a) { Reverse(a); return a; } templateT Uniqued(T a) { Unique(a); return a; } templateauto Max(const T& a) { return *max_element(all(a)); } templateauto Min(const T& a) { return *min_element(all(a)); } templateint MaxPos(const T& a) { return max_element(all(a)) - a.begin(); } templateint MinPos(const T& a) { return min_element(all(a)) - a.begin(); } templateint Count(const T& a, const U& v) { return count(all(a), v); } templateint Find(const T& a, const U& v) { auto pos = find(all(a), v); return pos == a.end() ? -1 : pos - a.begin(); } templateU Sum(const T& a, const U& v) { return accumulate(all(a), v); } templateint Lower(const T& a, const U& v) { return lower_bound(all(a), v) - a.begin(); } templateint Upper(const T& a, const U& v) { return upper_bound(all(a), v) - a.begin(); } templateint CountIf(const T& a, P f) { return count_if(all(a), f); } templatevoid RemoveIf(T& a, P f) { a.erase(remove_if(all(a), f), a.end()); } templateT Age(T n, T m) { return (n + m - 1) / m; } templateT Gcd(T n, T m) { return m ? Gcd(m, n % m) : n; } templateT Lcm(T n, T m) { return n / Gcd(n, m) * m; } templateT Pow(T a, T n) { T r = 1; while (n > 0) { if (n & 1)r *= a; a *= a; n /= 2; }return r; } templateT Powmod(T a, T n, T m = MOD) { T r = 1; while (n > 0) { if (n & 1)r = r * a % m, n--; else a = a * a % m, n /= 2; }return r; } string operator*(string s, int n) { string ret; rep(i, n)ret += s; return ret; } /* INPUT */ templateT InputF() { T ret; cin >> ret; return ret; } template<> char InputF() { char ret = '\0', c = getchar_unlocked(); while (c != '\0' && c != '\n' && c != '\t' && c != ' ') { ret = c; c = getchar_unlocked(); } return ret; } template<> string InputF() { string ret; char c = getchar_unlocked(); while (c != '\0' && c != '\n' && c != '\t' && c != ' ') { ret.push_back(c); c = getchar_unlocked(); } return ret; } template<> int InputF() { int ret = 0; bool neg = false; char c = getchar_unlocked(); if (c == '-') { neg = true; c = getchar_unlocked(); } while ('0' <= c && c <= '9') { ret = ret * 10 + (c - '0'); c = getchar_unlocked(); } return neg ? -ret : ret; } template<> LL InputF() { LL ret = 0; bool neg = false; char c = getchar_unlocked(); if (c == '-') { neg = true; c = getchar_unlocked(); } while ('0' <= c && c <= '9') { ret = ret * 10LL + (LL(c) - LL('0')); c = getchar_unlocked(); } return neg ? -ret : ret; } template<> double InputF() { double ret = 0, dp = 1; bool neg = false, adp = false; char c = getchar_unlocked(); if (c == '-') { neg = true; c = getchar_unlocked(); } while (('0' <= c && c <= '9') || c == '.') { if (c == '.') { adp = true; } else if (adp) { dp *= 0.1; ret += (c - '0') * dp; } else { ret = ret * 10.0 + (c - '0'); } c = getchar_unlocked(); } return neg ? -ret : ret; } string GetLine() { string ret; char c = getchar_unlocked(); while (c != '\0' && c != '\n') { ret.push_back(c); c = getchar_unlocked(); } return ret; } templateT Parse(string s) { return s; } template<> char Parse(string s) { return s.front(); } template<> string Parse(string s) { return s; } template<> int Parse(string s) { return stoi(s); } template<> LL Parse(string s) { return stoll(s); } template<> double Parse(string s) { return stod(s); } VS InputB; templatestruct InputC { operator T() { return InputF(); } vector operator[](int h) { vector ret(h); rep(i, h)ret[i] = InputF(); return ret; } vector> operator[](PII p) { int h, w; tie(h, w) = p; vector> ret(h, vector(w)); rep(i, h)rep(j, w)ret[i][j] = InputF(); return ret; } T operator()(int n) { while (sz(InputB) <= n)InputB.pb(InputF()); return Parse(InputB[n]); } vector operator()(int n, int h) { vector ret(h); rep(i, h)ret[i] = InputC::operator()(i + n); return ret; } vector> operator()(int n, int h, int w) { vector> ret(h, vector(w)); rep(i, h)rep(j, w)ret[i][j] = InputC::operator()(n + i * w + j); return ret; } }; InputC inc; InputC ins; InputC ini; InputC inl; InputC ind; /* OUTPUT */ class ostreamfbuff : public basic_streambuf> { protected:int overflow(int nCh = EOF) { putchar_unlocked(nCh); return 0; } }; class ostreamf : public basic_iostream> { public:ostreamf(void) : basic_iostream>(new ostreamfbuff()) {} }; ostreamf coutf; ostream& operator<<(ostream& ostr, InputC i) { ostr << string(i); return ostr; } struct BoolStr { string t, f; BoolStr(string _t, string _f) :t(_t), f(_f) {} }yes("yes", "no"), Yes("Yes", "No"), YES("YES", "NO"), Yay("Yay!", ":("); struct Divizer { string s; Divizer(string _s) :s(_s) {} }spc(" "), nosp(""), comma(","), lin("\n"); struct Output { bool flag = false; BoolStr bs; Divizer di; Output(bool f, BoolStr b, Divizer d) :flag(f), bs(b), di(d) {} templatevoid print(T o) { coutf << o; } void print(double o) { printf("%.20f", o); } void print(bool o) { coutf << (o ? bs.t : bs.f); } templatevoid print(const pair& o) { print(o.first); coutf << di.s; print(o.second); } templatevoid print(const vector& o) { for (int i = 0; i < (int)o.size(); ++i) { if (i != 0)coutf << di.s; print(o[i]); } } templatevoid print(const vector>& o) { for (int i = 0; i < (int)o.size(); ++i) { if (i != 0)coutf << '\n'; print(o[i]); } } templatevoid print(const map& o) { coutf << "Map"; for (auto a : o) { coutf << " {"; print(a); coutf << "},"; } coutf << '\n'; } templatevoid print(const set& o) { coutf << "Set {"; for (auto a : o) { print(a); coutf << ","; } coutf << "}\n"; } templateOutput operator ,(T o) { if (flag)coutf << di.s; print(o); Output t(true, bs, di); return t; } Output operator,(Output o) { coutf << '\n'; Output t(false, bs, di); return t; } Output operator,(BoolStr b) { Output t(flag, b, di); return t; } Output operator,(Divizer d) { Output t(flag, bs, d); return t; } }out(false, Yes, spc); /* ANSWER */ templatestruct Answer { T min, max, sum; int cnt; Answer() :min(numeric_limits::max()), max(numeric_limits::min()), sum(0), cnt(0) {} void operator=(T n) { min = std::min(min, n); max = std::max(max, n); sum += n; cnt++; } operator bool() { return cnt; } }; struct Point { int x, y; Point() :x(-1), y(-1) {} Point(int _x, int _y) :x(_x), y(_y) {} Point(int val, int h, int w) :x(val% w), y(val / w) {} Point operator+() { return *this; } Point operator-() { return { -x,-y }; } Point operator+(Point p) { return { x + p.x,y + p.y }; } Point operator-(Point p) { return { x - p.x,y - p.y }; } Point operator*(Point p) { return { x * p.x,y * p.y }; } Point operator/(Point p) { return { x / p.x,y / p.y }; } Point operator+(int d) { return { x + d,y + d }; } Point operator-(int d) { return { x - d,y - d }; } Point operator*(int d) { return { x * d,y * d }; } Point operator/(int d) { return { x / d,y / d }; } Point& operator+=(Point p) { x += p.x; y += p.y; return *this; } Point& operator-=(Point p) { x -= p.x; y -= p.y; return *this; } Point& operator*=(Point p) { x *= p.x; y *= p.y; return *this; } Point& operator/=(Point p) { x /= p.x; y /= p.y; return *this; } bool operator==(Point p) { return x == p.x && y == p.y; } bool operator!=(Point p) { return x != p.x || y != p.y; } int Dist(Point p) { return abs(x - p.x) + abs(y - p.y); } bool inBound(int H, int W) { return 0 <= x && x < W && 0 <= y && y < H; } array Adjacent4() { return { Point(x,y + 1),Point(x,y + -1),Point(x + 1,y),Point(x + -1,y) }; } array Adjacent8() { return { Point(x,y + 1),Point(x,y - 1),Point(x + 1,y),Point(x - 1,y), Point(x + 1,y + 1),Point(x + 1,y + -1),Point(x - 1,y + 1),Point(x - 1,y - 1) }; } templateauto& operator[](T& v) { return v[y][x]; } }; const int INF = 1'000'000'000; const long long INFLL = 1'000'000'000'000'000'000; using Weight=int; using P=pair; struct Edge { int to; Weight cost; }; struct Edge2 { int u, v; Weight cost; }; using Graph=vector>; bool Check(int a, int b, int c) { if (a == b || a == c || b == c) { return false; } else if ((a < b && c < b) || (a > b && c > b)) { return true; } else { return false; } } int main() { int n = ini, m = ini; VI a = ini[n]; vector e(m); rep(i, m)e[i] = mp(ini - 1, ini - 1); bool flag = false; rep(i, m)FOR(j, i + 1, m) { auto e1 = e[i], e2 = e[j]; int e11, e12, e21, e22; tie(e11, e12) = e1; tie(e21, e22) = e2; if (e11 == e21 && Check(a[e12], a[e11], a[e22])) { flag = true; } else if (e11 == e22 && Check(a[e12], a[e11], a[e21])) { flag = true; } else if (e12 == e21 && Check(a[e11], a[e12], a[e22])) { flag = true; } else if (e12 == e22 && Check(a[e11], a[e12], a[e21])) { flag = true; } } out, YES, flag, out; }