python/LuoGu/RuMen/P2043.cpp

#include <bits/stdc++.h>

using namespace std;
int a[10001] = {0}, n; //数组很大，记得开在外面哦
int main() {
    ios::sync_with_stdio(false); //读入输出优化的强迫症
    cin >> n;
    //1就不用了，从2到n一个一个来
    for (int i = 2; i <= n; i++) {
        //备份一下，不然等会被除掉了
        int i2 = i;
        //从2开始判断是否可以整除
        for (int j = 2; j <= i; j++)
            while (i2 % j == 0) {
                a[j]++;
                i2 /= j;
            }
    }
    for (int i = 1; i <= 10000; i++)  //输出
        if (a[i] != 0) {
            cout << i << " " << a[i] << endl;
        }
}