#include <bits/stdc++.h>
#define fr first
#define sc second
#define all(a) (a).begin(), (a).end()
#define unique(a) a.resize(unique(a.begin(), a.end()) - a.begin())

using namespace std;

#ifdef ONPC
mt19937 rnd(223);
#else
mt19937 rnd(chrono::high_resolution_clock::now()
			.time_since_epoch().count());
#endif

#define TIME (clock() * 1.0 / CLOCKS_PER_SEC)

using ll = long long;
using lll = __int128;
using ld = long double;

const int maxn = 1e6 + 100, inf = 1e9 + 100;

const lll mod = lll(1e9+7)*lll(1e9+9);
const lll pmod = lll(1e9+6)*lll(1e9+8);

lll po(lll a,lll b) {
    lll ans = 1;
    for(a%=mod;b;b>>=1,a=a*a%mod)if(b&1)ans=ans*a%mod;
    return ans;
}

lll inv(lll x) {
    return po(x,pmod-1);
}

ll p[maxn], q[maxn];
lll msum[maxn];

void solve() {
    int n;
    cin >> n;
    ld dsum = 0;
    map<lll,ll> ct;
    for(int i=1;i<=n;i++) {
//        cerr << i << endl;
        cin >> p[i] >> q[i];
        lll mv = p[i]*inv(q[i])%mod;
        dsum += ld(p[i])/q[i];
        lll adj = roundl(dsum);
        mv-=adj;
        dsum-=adj;
        msum[i]=(msum[i-1]+mv)%mod;
        if(msum[i]<0)msum[i]+=mod;
        ct[msum[i]]++;
//        cerr << ll(msum[i]) << endl;
    }
    ct[0]++;
    ll ans = 0;
    for(auto [v,x] : ct) {
//        cerr << ll(v) << " " << x << endl;
        ans += x*(x-1+(ct.count((v+mod-1)%mod)?ct[(v+mod-1)%mod]:0)+(ct.count(v+1%mod)?ct[(v+1)%mod]:0));
    }
    cout << ans /2 << "\n";
}

int main() {
#ifdef ONPC
    freopen("../a.in", "r", stdin);
//    freopen("../a.out", "w", stdout);
#endif
    ios::sync_with_stdio(0);
    cin.tie(0);
    cout << fixed;
    cout.precision(20);
    solve();
    cerr << "\n\nConsumed " << TIME << endl;
}