分解质因数,求每个数指数,指数的gcd即是最大的p

#include<bits/stdc++.h>
using namespace std;
#define fst first
#define sec second
#define sci(num) scanf("%d",&num)
#define scl(num) scanf("%lld",&num)
#define mem(a,b) memset(a,b,sizeof a)
#define cpy(a,b) memcopy(a,b,sizeof b)
typedef long long LL;
typedef pair<int,int> P;
const int MAX_N = 1e7 + 100;
const int MAX_M = 1e6;
bool isp[MAX_N];
int primes[MAX_M];
void init() {
    for (int i =2 ;i < MAX_N;i++) {
        if (!isp[i]) {
            primes[++primes[0]] = i;
            for (int j = i + i;j < MAX_N;j+= i) {
                isp[j] = true;
            }
        }
    }
}
LL sum(LL N) {
    bool neg = false;
    if (N < 0) N = - N,neg = -1;
    LL ans = 0;
    for (int i = 1;i <= primes[0] && N != 1 && N >= primes[i];i++) {
        LL loc = 0;
        while (N  % primes[i] == 0 && N != 1) {
            N /= primes[i];
            loc++;
        }
        ans = __gcd(ans,loc);
    }
    if (N > 1) ans = 1;
    if (neg) {
        while (ans % 2 == 0)
            ans /= 2;
    }
    return ans;
}
int main() {
    init();
    int T;
    sci(T);
    for (int cs = 1;cs <= T;cs++) {
        LL N;
        scl(N);
        printf("Case %d: %lld\n",cs,sum(N));
    }
    return 0;
}