Sample Input

97532468

Sample Output

97532468=2^2*11*17*101*1291

思路：
int范围大概sqrt后是5e5，我打的表比较小但够了。
注意最后输入的数为素数时的情况，最后两个点就是素数和1.
代码

#include <iostream>
#include <algorithm>
#include <cstdio>
#include <string>
#include <cstring>
#include <cmath>

using namespace std;

#define endl '\n'

typedef long long ll;

ll a[100005];

void Prime()
{
    a[1] = 1;
    for (int i = 2; i <= 100000; ++i)
    {
        if (!a[i])
            for (int j = 2 * i; j <= 100000; j += i)
            {
                a[j] = 1;
            }
    }
}

int main()
{
    Prime();

    ll n;

    cin >> n;

    cout << n << "=";


    int f = 0;

    ll m = n;

    for (ll i = 1; i <= sqrt(m); ++i)
    {
        if (a[i] == 0 && n % i == 0)
        {
            if (f == 0) f = 1;
            else cout << "*";
            ll cnt = 0;
            cout << i;
            while (n % i == 0)
            {
                cnt++;
                n /= i;
            }
            if (cnt > 1)
            {
                cout << "^" << cnt;
            }
        }
        if(n == 1) break;
    }

    if (f == 0)
    {
        cout << n;
    }

    // getchar(); getchar();

    return 0;
}