#pragma GCC target ("avx2")
#pragma GCC optimize ("O3")
#pragma GCC optimize ("unroll-loops")
#include<bits/stdc++.h>
#include<math.h>
using namespace std;
typedef long long int ll;
typedef long double ld;
typedef pair<ll, ll> pl;
typedef vector<ll> vl;
#define FD(i, r, l) for(ll i = r; i > (l); --i)
#define K first
#define V second
#define G(x) ll x; cin >> x;
#define GD(x) ld x; cin >> x;
#define GS(s) string s; cin >> s;
#define EX(x) { cout << x << '\n'; exit(0); }
#define A(a) (a).begin(), (a).end()
#define F(i, l, r) for (ll i = l; i < (r); ++i)
#define NN
#define M 1000000007 // 998244353
int main(){
// freopen("a.in", "r", stdin);
// freopen("a.out", "w", stdout);
ios_base::sync_with_stdio(false); cin.tie(0);
cout << fixed << setprecision(20);
G(n)
vector<pl> a(n);
ll ans = 0;
for (auto &[x, y]: a) {
cin >> x >> y;
ans += x==y;
}
EX(ans)
}
