#include <iostream>
using namespace std;
 
int n;
int d, w;
 
int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
 
    cin >> n;
    int stack[n];
    int top = -1;
    int wynik = 0;
 
    for (int i = 0; i < n; i++) {
        cin >> d >> w;
 
        while (top >= 0 && stack[top] > w) {
            top--;
        }
 
        if (top < 0 || stack[top] < w) {
            stack[++top] = w;
            wynik++;
        }
    }
 
    cout << wynik << '\n';
    return 0;
}

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NQoxIDIKMSAzCjIgMgoyIDUKMSA0

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