Treasure Hunting

#include <iostream>
#include <algorithm>
#include <math.h>
using namespace std;

__int64 max(__int64 a, __int64 b)
{
    return a > b ? a : b;
}
int a[25] = {2, 3, 5, 7, 11, 13, 17, 19, 23,
 29, 31, 37, 41, 43, 47, 53, 59,
  61, 67, 71, 73,79, 83, 89, 97};
__int64 num[25];
int total;

void fun(int x, __int64 y)
{
    for(int i = 0; i < 25 && x != 1; ++i)
    {
        while(x % a[i] == 0)
        {
            x /= a[i];
            if(num[i] == 0)
                total++;
            num[i] += y;
        }
    }
}

__int64 NumOfX(__int64 n, __int64 x)
{
    __int64 ans = 0;
    while(n)
    {
        ans += n / x;
        n /= x;        
    }
    return ans;
}

int main()
{
    //init();
    int cas, n, num1;
    __int64 num2;
    cin >> cas;
    while(cas--)
    {
        __int64 count = 1;
        total = 0;
        memset(num, 0, sizeof(num));
        scanf("%d", &n);
        while(n--)
        {
            scanf("%d%I64d", &num1, &num2);
            fun(num1, num2);
        }
        __int64 l = 2, r = 0, mid;
        for(int i = 0; i < 25; ++i)
            r = max(r, a[i] * num[i]);
        r = max(r, r);
        while(l + 1 < r)
        {
            mid = (l + r) / 2;
            bool flag = true;
            for(int i = 0; i < 25 && flag; ++i)
            {
                if(NumOfX(mid, a[i]) < num[i])
                    flag = false;
            }
            if(flag)
                r = mid;
            else 
                l = mid;
            /*
            int temp = mid;
            int tt = total;
            for(int i = 0; i < 25 && temp != 1; ++i)
            {
                while(temp % a[i] == 0)
                {
                    temp /= a[i];
                    num[i]--;
                    if(num[i] == 0)
                        tt--;
                }
            }
            if(tt == 0)
                r = mid;
            else 
                l = mid;
            */
        }
        printf("%I64d\n", r);
    }
    //getchar();
    return 0;
}
/*
6
2
3 2
4 1

3
3 2
1 4
2 2

2
45 123
67 23

8
12 11000000046
23 10000004567
45 110000000
7 10000000076
9 1100000576
9 100000000657
24 110000067
42 1000000000

*/

　二分啊~~　

   还是弱爆了。。。