超级入口！

很不错的板子题。
太简单了无讲解= =

附两道板子题待刷
poj2891，n个mi不互质的裸题
poj1006，三个互质的裸题

#include <bits/stdc++.h>
#define inf 0x7fffffff
#define ll long long
#define int long long
//#define double long double
//#define double long long
#define re int
//#define void inline void
#define eps 1e-8
//#define mod 1e9+7
#define ls(p) p<<1
#define rs(p) p<<1|1
#define pi acos(-1.0)
#define pb push_back
#define mk make_pair
#define P pair < int , int >
using namespace std;
const int mod=1e9+7;
//const int inf=1e18;
const int M=1e8;
const int N=3;//??????.???? 4e8
int n;
int a[100005];
int b[100005];

int exgcd(int a,int b,int &x,int &y)
{
	if(!b)
	{
		x=1;y=0;
		return a;
	}
	else
	{
		int tx,ty;
		int d=exgcd(b,a%b,tx,ty);
		x=ty;y=tx-(a/b)*ty;
		return d;
	}
}

int China(int a[],int b[],int n)
{
    int M=1,y,x=0;
    for(int i=1;i<=n;++i)
        M*=a[i];
    for(int i=1;i<=n;++i)
    {
        int w=M/a[i];
        int tx=0;
        int t=exgcd(w,a[i],tx,y);
        x=(x+w*(b[i]/t)*tx)%M; 
    }
    return (x+M)%M;
}

void solve()
{
	cin>>n;
    for(int i=1;i<=n;i++)
    {
    	cin>>a[i]>>b[i];
	}
	int ans=China(a,b,n);
	cout<<ans<<endl;
}
signed main()
{
    int T=1;       
//    cin>>T;
    for(int index=1;index<=T;index++)
    {
        solve();
//        puts("");
    }
    return 0;
}
/*
input:
3
3 1
5 1
7 2
output:16
*/