C++ 解法, 执行用时: 548ms, 内存消耗: 10016K, 提交时间: 2023-08-12 10:10:45

#include <iostream>
#include <cstring>
#include <algorithm>
#define int long long

using namespace std;

const int p = 1e9 + 7;
int n, m;

inline void read(int &x) {  // 返回类型必须为void，否则竞赛中Linux测评会报错，Windows没事
	x = 0;
	short flag = 1;
	char c = getchar();
    while(c < '0' || c > '9'){
    	// 此处如果只用if的话容易在数据不规范时出错，特别是cin和read混用
        if(c == '-')flag = -1;
        c = getchar();
    }
	while(c >= '0' && c <= '9') {
		x = (x << 3) + (x << 1) + (c ^ 48);  // 48这个数字恰好往后10个数都可以使用位运算，可以写成二进制证明；位运算能用当然更好
		c = getchar();
	}
	x *= flag;
}

int qmi(int a, int b, int p)
{
	int res = 1;
	while(b)
	{
		if(b & 1) res = res * a % p;
		b >>= 1;
		a = a * a % p;
	}
	
	return res % p;
}

signed main()
{
	int T;
	read(T);
	
	while( T -- )
	{
		read(n);
		read(m);
		
		int pown = qmi(n, m, p);
		int inv = qmi(pown, p - 2, p);
		
		int ans = ((pown - 1) * inv) % p;
		printf("%lld\n", ans);
	}
    
    return 0;
}

Java 解法, 执行用时: 2290ms, 内存消耗: 28036K, 提交时间: 2023-08-12 10:10:00

import java.io.*;
import java.math.*;
import java.util.*;
 
    
public class Main {
	public static void main(String[] args) throws IOException {
		int t=nextInt();
		long mod=1000000007;
		while(t-->0) {
			int n=nextInt(),m=nextInt();
			long res=qpow(n,m,mod);
			long ans=qpow(res,mod-2,mod);
			out.println((1-ans+mod)%mod);
		}
        out.flush();
    }
	public static long qpow(long a,long b,long mod) {
		long res=1;
		while(b>0) {
			if(b%2==1)res=(res*a)%mod;
			b>>=1;
			a=(a*a)%mod;
		}
		return res;
	}
	static Scanner scan =new Scanner(System.in);
    static PrintWriter out =new PrintWriter(new OutputStreamWriter(System.out));
	static StreamTokenizer in =new StreamTokenizer(new BufferedReader(new InputStreamReader(System.in)));
	public static int nextInt() throws IOException {in.nextToken();return (int)in.nval;}
	public static double nextDouble() throws IOException {in.nextToken();return in.nval;}
	public static float nextFloat() throws IOException {in.nextToken();return (float) in.nval;}
	public static String next() throws IOException {in.nextToken();return in.sval;}
}