View Code of Problem 2594

#include<stdio.h>
#define ll long long int 

const int MK = 100005;
const int N = 1005; 
int b;
ll n, a[N];
 
ll cal(ll n) {                    
    ll ret = 0;
    for (int i = 0; i < b; ++i) {
        ret += (n - 1 + a[i]) / a[i];   
    }
    return ret;
}
 
int main() {
    int T, i, j, k;
    scanf("%d",&T);
    while (T--) {
       scanf("%d%d",&b,&n);
        for (i = 0; i < b; ++i) {
            scanf("%d",&a[i]);
        }
        ll l = 0, r = n * MK;
        while (l < r) {
            ll mid = l + r >> 1;
            if (cal(mid) < n) {
                l = mid + 1;
            } else {
                r = mid;
            }
        }
        int last = cal(l - 1), ans = 0;
        for (i = 0; i < b; ++i) {
            if ((l - 1) % a[i] == 0) {
                ++last;
                if (last == n) {
                    ans = i + 1;
                    break;
                }
            }
        }
        static int numCase = 0;
       printf("Case #%d: %d\n",++numCase,ans );

    }
    return 0;
}