func_code_string: #include <bits/stdc++.h>   using namespace std;   const int N = 1e5 + 10;   int n, L, a;   int t[N], l[N];   int main() {     ios_base::sync_with_stdio(false);     cin.tie(0);     cout.tie(0);     srand(time(NULL));     cin >> n >> L >> a;     int res = 0;     for (int i = 1; i <= n; i++) {       cin >> t[i] >> l[i];       int len = t[i] - (t[i - 1] + l[i - 1]);       res += len / a;     }     res += (L - (t[n] + l[n])) / a;     cout << res;   }   