| # |
제출 시각 |
아이디 |
문제 |
언어 |
결과 |
실행 시간 |
메모리 |
| 20080 |
2016-02-25T10:39:15 Z |
sui |
Σ (kriii4_P2) |
C++14 |
|
19 ms |
1884 KB |
#define _CRT_SECURE_NO_WARNINGS // scanf(), gets() (needed for Visual C++)
//#define NDEBUG
#include <cassert>
#include <iostream>
#include <cstdio>
#include <cstring>
#include <cmath>
#include <algorithm>
#include <functional>
#include <string>
#include <vector>
#include <queue>
#include <set>
#include <map>
#include <unordered_map>
#include <stack>
#include <deque>
using namespace std;
#define MEMSET(x, WITH) memset(x, (WITH), sizeof(x))
#define FOR(i, E) for(int i=0; i<(E); i++)
#define REP(i, LO, HI) for(int i=(LO); i<=(HI); i++)
#define GETINT(x) scanf("%d", &x)
#define GETDBL(x) scanf("%lf", &x)
#define GETSTR(x) scanf("%s", x)
#define NEWINT(x) int x; scanf("%d", &x)
#define NEWDBL(x) double x; scanf("%lf", &x)
#define NEWLN putchar('\n')
#ifdef _WIN32
#define popcnt __popcnt
#else
#define popcnt __builtin_popcount
#endif
typedef long long ll;
//const ll MOD = 1000000007;
//const double PI = atan(1) * 4;
const ll MOD = 1000000007;
ll powerMod(ll a, ll n) {
ll ans = 1;
for (int i=62; i>=0; i--) {
ans = ans * ans % MOD;
if ((n>>i)&1)
ans = ans * a % MOD;
}
return ans;
}
ll a[10333];
ll b[10333];
ll ans;
int main() {
int M; cin >> M;
FOR(i, M) cin >> b[i] >> a[i];
ll denom = 1;
FOR(i, M) denom = denom * b[i] % MOD;
ll numer = 0;
FOR(i, M) {
ll n = a[i] * denom % MOD * powerMod(b[i], MOD-2) % MOD;
numer = (numer + n) % MOD;
}
ans = numer * powerMod(denom, MOD-2) % MOD;
cout << ans << endl;
/*
ans = 0;
FOR(i, M) {
ll term = a[i] * powerMod(b[i], MOD-2) % MOD;
ans += term;
ans %= MOD;
}
cout << ans << endl;
*/
return 0;
}
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Correct |
19 ms |
1884 KB |
Output is correct |
| 2 |
Correct |
14 ms |
1884 KB |
Output is correct |
| 3 |
Correct |
17 ms |
1884 KB |
Output is correct |
| 4 |
Correct |
9 ms |
1884 KB |
Output is correct |
| 5 |
Correct |
15 ms |
1884 KB |
Output is correct |
| 6 |
Correct |
11 ms |
1884 KB |
Output is correct |
| 7 |
Correct |
14 ms |
1884 KB |
Output is correct |
| 8 |
Correct |
14 ms |
1884 KB |
Output is correct |
| 9 |
Correct |
19 ms |
1884 KB |
Output is correct |
| 10 |
Correct |
15 ms |
1884 KB |
Output is correct |
| 11 |
Correct |
18 ms |
1884 KB |
Output is correct |
| 12 |
Correct |
18 ms |
1884 KB |
Output is correct |
| 13 |
Correct |
14 ms |
1884 KB |
Output is correct |
| 14 |
Correct |
19 ms |
1884 KB |
Output is correct |
| 15 |
Correct |
15 ms |
1884 KB |
Output is correct |
| 16 |
Correct |
12 ms |
1884 KB |
Output is correct |
| 17 |
Correct |
13 ms |
1884 KB |
Output is correct |
| 18 |
Correct |
16 ms |
1884 KB |
Output is correct |
| 19 |
Correct |
19 ms |
1884 KB |
Output is correct |
| 20 |
Correct |
13 ms |
1884 KB |
Output is correct |
