func_code_string: #include <bits/stdc++.h>   using namespace std;   int dx[4] = {1, 0, -1, 0};   int dy[4] = {0, 1, 0, -1};   int ddx[8] = {-1, -1, 0, 1, 1, 1, 0, -1};   int ddy[8] = {0, 1, 1, 1, 0, -1, -1, -1};   bool debug = false;   int main() {     int n, L, a;     cin >> n >> L >> a;     int ans = 0, now = 0;     for (int i = 0; i < n; i++) {       int t, l;       cin >> t >> l;       ans += (t - now) / a;       now = t + l;     }     ans += (L - now) / a;     cout << ans << endl;     return 0;   }   