func_code_string: #include <bits/stdc++.h>   using namespace std;   const int maxn = 1e5 + 5;   int a[maxn];   int n, x, k;   int main() {     ios::sync_with_stdio(0);     cin.tie(0);     cout.tie(0);     cin >> n >> x >> k;     for (int i = 0; i < n; i++) cin >> a[i];     sort(a, a + n);     long long ans = 0;     for (int i = 0; i < n; i++) {       long long l = (a[i] - 1) / x;       long long r = l + k;       ans += (long long)(lower_bound(a, a + n, (r + 1) * x) -                          lower_bound(a, a + n, max(r * x, (long long)a[i])));     }     cout << ans << endl;     return 0;   }   