Submission #19332

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
19332	2016-02-24T09:55:17 Z	exqt	Σ (kriii4_P2)	C++	100 / 100	28 ms	2000 KB

P2

#include <iostream>
#include <cstdio>
#include <vector>
#include <algorithm>
#include <utility>
#include <queue>
#include <string>
#include <cstring>
#include <map>
using namespace std;

#define in cin
#define out cout
#define ll long long int

ll DV = 1000000007;
ll mypow(ll a, ll b)
{
    ll t = a;
    ll res = 1;
    while(b)
    {
        if(b%2) res = (res * t) % DV;
        t = t % DV;
        t = (t*t) % DV;
        b = b >> 1;
    }

    return res;
}

ll myinv(ll a)
{
    return mypow(a, DV-2);
}

int main()
{
    int n; in >> n;
    ll mb = 1;
    vector<ll> va, vb;
    for(int i=0; i<n; i++)
    {
        ll a, b; in >> b >> a;
        va.push_back(a);
        vb.push_back(b);
        mb *= b; mb %= DV;
    }

    ll u = 0;
    for(int i=0; i<n; i++)
    {
        u += ((va[i]%DV)*(mb%DV)%DV)*(myinv(vb[i])%DV);
        u %= DV;
    }

    out << (u)*(myinv(mb))%DV;

    return 0;
}

Subtask #1

100.0 / 100.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	28 ms	2000 KB	Output is correct
2	Correct	24 ms	2000 KB	Output is correct
3	Correct	24 ms	2000 KB	Output is correct
4	Correct	23 ms	2000 KB	Output is correct
5	Correct	28 ms	2000 KB	Output is correct
6	Correct	23 ms	2000 KB	Output is correct
7	Correct	27 ms	2000 KB	Output is correct
8	Correct	24 ms	2000 KB	Output is correct
9	Correct	23 ms	2000 KB	Output is correct
10	Correct	27 ms	2000 KB	Output is correct
11	Correct	26 ms	2000 KB	Output is correct
12	Correct	26 ms	2000 KB	Output is correct
13	Correct	24 ms	2000 KB	Output is correct
14	Correct	28 ms	2000 KB	Output is correct
15	Correct	23 ms	2000 KB	Output is correct
16	Correct	22 ms	2000 KB	Output is correct
17	Correct	28 ms	2000 KB	Output is correct
18	Correct	28 ms	2000 KB	Output is correct
19	Correct	26 ms	2000 KB	Output is correct
20	Correct	27 ms	2000 KB	Output is correct