結果
| 問題 |
No.1081 和の和
|
| コンテスト | |
| ユーザー |
 mikit
|
| 提出日時 | 2020-06-19 23:20:12 |
| 言語 | Java (openjdk 23) |
| 結果 |
WA
|
| 実行時間 | - |
| コード長 | 9,221 bytes |
| コンパイル時間 | 2,741 ms |
| コンパイル使用メモリ | 82,076 KB |
| 実行使用メモリ | 50,576 KB |
| 最終ジャッジ日時 | 2024-07-03 15:44:31 |
| 合計ジャッジ時間 | 3,573 ms |
|
ジャッジサーバーID （参考情報） |
judge1 / judge2 |
（要ログイン）
| ファイルパターン | 結果 |
|---|---|
| sample | AC * 3 |
| other | AC * 3 WA * 5 |
ソースコード
import java.io.OutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.Arrays;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.BufferedOutputStream;
import java.io.UncheckedIOException;
import java.util.Objects;
import java.nio.charset.Charset;
import java.util.StringTokenizer;
import java.io.Writer;
import java.io.OutputStreamWriter;
import java.io.BufferedReader;
import java.io.InputStream;
/**
* Built using CHelper plug-in
* Actual solution is at the top
*
* @author mikit
*/
public class Main {
public static void main(String[] args) {
InputStream inputStream = System.in;
OutputStream outputStream = System.out;
LightScanner in = new LightScanner(inputStream);
LightWriter out = new LightWriter(outputStream);
Task solver = new Task();
solver.solve(1, in, out);
out.close();
}
static class Task {
private static final int MOD = (int) 1e9 + 7;
public void solve(int testNumber, LightScanner in, LightWriter out) {
int n = in.ints();
ModMath mod = new ModMath(MOD);
Factorial fact = mod.getFactorial(n);
long ans = 0;
for (int i = 0; i < n; i++) ans += in.longs() * fact.ncr(n - 1, i);
out.ans(ans % MOD).ln();
}
}
static class LightScanner implements AutoCloseable {
private BufferedReader reader = null;
private StringTokenizer tokenizer = null;
public LightScanner(InputStream in) {
reader = new BufferedReader(new InputStreamReader(in));
}
public String string() {
while (tokenizer == null || !tokenizer.hasMoreTokens()) {
try {
tokenizer = new StringTokenizer(reader.readLine());
} catch (IOException e) {
throw new UncheckedIOException(e);
}
}
return tokenizer.nextToken();
}
public int ints() {
return Integer.parseInt(string());
}
public long longs() {
return Long.parseLong(string());
}
public void close() {
try {
this.reader.close();
} catch (IOException ex) {
throw new UncheckedIOException(ex);
}
}
}
static class Vec3l implements Comparable<Vec3l> {
public long x;
public long y;
public long z;
public Vec3l(long x, long y, long z) {
this.x = x;
this.y = y;
this.z = z;
}
public boolean equals(Object o) {
if (this == o) return true;
if (o == null || getClass() != o.getClass()) return false;
Vec3i vec3i = (Vec3i) o;
return x == vec3i.x &&
y == vec3i.y &&
z == vec3i.z;
}
public int hashCode() {
return Objects.hash(x, y, z);
}
public String toString() {
return "(" + x + ", " + y + ", " + z + ")";
}
public int compareTo(Vec3l o) {
if (x == o.x) {
if (y == o.y) {
return Long.compare(z, o.z);
}
return Long.compare(y, o.z);
}
return Long.compare(x, o.x);
}
}
static class Vec3i implements Comparable<Vec3i> {
public int x;
public int y;
public int z;
public Vec3i(int x, int y, int z) {
this.x = x;
this.y = y;
this.z = z;
}
public boolean equals(Object o) {
if (this == o) return true;
if (o == null || getClass() != o.getClass()) return false;
Vec3i vec3i = (Vec3i) o;
return x == vec3i.x &&
y == vec3i.y &&
z == vec3i.z;
}
public int hashCode() {
return Objects.hash(x, y, z);
}
public String toString() {
return "(" + x + ", " + y + ", " + z + ")";
}
public int compareTo(Vec3i o) {
if (x == o.x) {
if (y == o.y) {
return Integer.compare(z, o.z);
}
return Integer.compare(y, o.z);
}
return Integer.compare(x, o.x);
}
}
static class LightWriter implements AutoCloseable {
private final Writer out;
private boolean autoflush = false;
private boolean breaked = true;
public LightWriter(Writer out) {
this.out = out;
}
public LightWriter(OutputStream out) {
this(new OutputStreamWriter(new BufferedOutputStream(out), Charset.defaultCharset()));
}
public LightWriter print(char c) {
try {
out.write(c);
breaked = false;
} catch (IOException ex) {
throw new UncheckedIOException(ex);
}
return this;
}
public LightWriter print(String s) {
try {
out.write(s, 0, s.length());
breaked = false;
} catch (IOException ex) {
throw new UncheckedIOException(ex);
}
return this;
}
public LightWriter ans(String s) {
if (!breaked) {
print(' ');
}
return print(s);
}
public LightWriter ans(long l) {
return ans(Long.toString(l));
}
public LightWriter ln() {
print(System.lineSeparator());
breaked = true;
if (autoflush) {
try {
out.flush();
} catch (IOException ex) {
throw new UncheckedIOException(ex);
}
}
return this;
}
public void close() {
try {
out.close();
} catch (IOException ex) {
throw new UncheckedIOException(ex);
}
}
}
static class ModMath {
private static final int DEFAULT_MOD = 1_000_000_007;
private final long mod;
public ModMath(long mod, boolean unsafe) {
/*if (!unsafe && !IntMath.isPrime(mod)) {
throw new RuntimeException("This class is designed for primes!");
}*/
this.mod = mod;
}
public ModMath(long mod) {
this(mod, false);
}
public ModMath() {
this(DEFAULT_MOD, true);
}
public long mod(long x) {
x %= mod;
return x < 0 ? x + mod : x;
}
public long inv(long x) {
//return pow(x, mod - 2);
return mod(LongEuclidSolver.solve(x, mod).x);
}
public Factorial getFactorial(int n) {
return new Factorial(this, n);
}
}
static class Factorial {
private final ModMath mod;
private final long[] natural;
private final long[] reverse;
public Factorial(ModMath mod, int max) {
this.mod = mod;
this.natural = new long[max];
this.reverse = new long[max];
natural[0] = 1;
for (int i = 1; i < max; i++) {
natural[i] = mod.mod(natural[i - 1] * i);
}
reverse[max - 1] = mod.inv(natural[max - 1]);
for (int i = max - 1; i > 0; i--) {
reverse[i - 1] = mod.mod(reverse[i] * i);
}
}
public long fact(long x) {
return natural[(int) x];
}
public long factinv(long x) {
return reverse[(int) x];
}
public long npr(long n, long r) {
return n < r ? 0 : mod.mod(fact(n) * factinv(n - r));
}
public long ncr(long n, long r) {
return mod.mod(npr(n, r) * factinv(r));
}
public String toString() {
return "Factorial{" +
"natural=" + Arrays.toString(natural) +
", reverse=" + Arrays.toString(reverse) +
'}';
}
}
static class LongEuclidSolver {
private LongEuclidSolver() {
}
public static Vec3l solve(long a, long b) {
LongEuclidSolver.ReferenceLong p = new LongEuclidSolver.ReferenceLong(), q = new LongEuclidSolver.ReferenceLong();
long d = solve(a, b, p, q);
return new Vec3l(p.val, q.val, d);
}
private static long solve(long a, long b, LongEuclidSolver.ReferenceLong p, LongEuclidSolver.ReferenceLong q) {
if (b == 0) {
p.val = 1;
q.val = 0;
return a;
} else {
long d = solve(b, a % b, q, p);
q.val -= (a / b) * p.val;
return d;
}
}
private static class ReferenceLong {
private long val;
}
}
}