#include<bits/stdc++.h>
#define ff first
#define ss second
#define pb push_back
typedef long long ll;
using namespace std;
typedef pair<int,int> pii;

int mod;
inline int add(int x,int y){int ret=x+y;if(ret>=mod)ret-=mod;return ret;}
inline int sub(int x,int y){int ret=x-y;if(ret<0)ret+=mod;return ret;}
inline int mul(int x,int y){return ((ll)x*y)%mod;}
inline int step(int base,int pw){int ret=1;while(pw){if(pw&1)ret=mul(ret,base);base=mul(base,base);pw>>=1;}return ret;}
inline int invv(int x){return step(x,mod-2);}


const int maxn=2e5+10;
/*const int nmods=2;/// must be even
int mods[nmods]={998244353,(int)1e9+7,(int)1e9+9,993192119,1000000861,1000001053};*/
const int nmods=2;/// must be even
int mods[nmods]={998244353,(int)1e9+7};

struct pt{

    int a[nmods];

    pt(){memset(a,0,sizeof(a));}
    pt(int p,int q){
        for(int i=0;i<nmods;i++){
            mod=mods[i];
            a[i]=mul(p,invv(q));
        }
    }

    pt operator +(pt b){

        pt ret;
        for(int i=0;i<nmods;i++){
            mod=mods[i];
            ret.a[i]=add(a[i],b.a[i]);
        }
        return ret;
    }
    pt operator -(pt b){

        pt ret;
        for(int i=0;i<nmods;i++){
            mod=mods[i];
            ret.a[i]=sub(a[i],b.a[i]);
        }
        return ret;
    }

    ll get_diagonal(){
        ll ret=0;
        for(int i=0;i<nmods;i++){
            if(i%2==0)ret+=a[i];
            else ret-=a[i];
        }
        return ret;
    }

}niz[maxn];

void ubaci(pt p,map<ll,ll>&mapa){

    for(int i=0;i<(1<<nmods);i++){

        pt np=p;
        for(int j=0;j<nmods;j++){
            if(i&(1<<j)){}
            else np.a[j]-=mods[j];
        }

       /// printf("%lld added\n",diag);

        mapa[np.get_diagonal()]++;

    }

}

int main(){

    ///freopen("test.txt","r",stdin);

    int n;
    scanf("%d",&n);
    for(int i=1;i<=n;i++){
        int p,q;
        scanf("%d %d",&p,&q);
        niz[i]=pt(p,q);
        niz[i]=niz[i-1]+niz[i];
    }

    map<ll,ll>mapa;
    ubaci(niz[0],mapa);

    ll rez=0;
    for(int i=1;i<=n;i++){
        ///printf("%lld DIAG %lld\n",niz[i].get_diagonal(),mapa[niz[i].get_diagonal()]);
        rez+=mapa[niz[i].get_diagonal()];
        ubaci(niz[i],mapa);
    }
    printf("%lld\n",rez);

    return 0;
}