#include <iostream>
const int LN = 1000000007;
int modpow( long long A, long long X )
{
int acc = 1;
while(X)
{
A %= LN;
if(X%2)
acc = (A*acc)%LN;
A = A*A;
X /= 2;
}
return acc;
}
int main()
{
int M;
while( std::cin >> M )
{
int N, S, acc = 0;
for( int i = 0; i < M; ++i )
{
std::cin >> N >> S;
int rev = modpow(N, LN-2);
int ans = ((long long)S*rev)%LN;
acc = (acc+ans)%LN;
}
std::cout << acc << std::endl;
}
return 0;
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
13 ms |
1720 KB |
Output is correct |
2 |
Correct |
14 ms |
1720 KB |
Output is correct |
3 |
Correct |
14 ms |
1720 KB |
Output is correct |
4 |
Correct |
13 ms |
1720 KB |
Output is correct |
5 |
Correct |
13 ms |
1720 KB |
Output is correct |
6 |
Correct |
14 ms |
1720 KB |
Output is correct |
7 |
Correct |
14 ms |
1720 KB |
Output is correct |
8 |
Correct |
15 ms |
1720 KB |
Output is correct |
9 |
Correct |
15 ms |
1720 KB |
Output is correct |
10 |
Correct |
11 ms |
1720 KB |
Output is correct |
11 |
Correct |
14 ms |
1720 KB |
Output is correct |
12 |
Correct |
13 ms |
1720 KB |
Output is correct |
13 |
Correct |
13 ms |
1720 KB |
Output is correct |
14 |
Correct |
15 ms |
1720 KB |
Output is correct |
15 |
Correct |
13 ms |
1720 KB |
Output is correct |
16 |
Correct |
12 ms |
1720 KB |
Output is correct |
17 |
Correct |
15 ms |
1720 KB |
Output is correct |
18 |
Correct |
11 ms |
1720 KB |
Output is correct |
19 |
Correct |
15 ms |
1720 KB |
Output is correct |
20 |
Correct |
13 ms |
1720 KB |
Output is correct |