#include<stdio.h>
#define M 1000000007
#define mod(a) ((a)%1000000007)
typedef long long int lld;
lld pow(lld a, lld x) {
if(!x) return 1;
lld P = pow(a, x/2);
if(x&1) return mod(a*mod(P*P));
return mod(P*P);
}
lld inv(lld a) {
return pow(a, M-2);
}
lld div(lld a, lld b) {
return mod(a*inv(b));
}
int main() {
int n;
scanf("%d", &n);
lld res = 0;
for(int i = 0; i < n; ++i) {
int N, S;
scanf("%d%d", &N, &S);
res += div(S, N);
}
printf("%lld\n", res);
return 0;
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
0 ms |
1084 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |