#include <stdio.h>
int stairs[100000] = {0};
int M, K, H;
long long total = 0;

int main() {
    scanf("%d %d %d", &M , &K, &H);
    // stairs = new int[M];
    for (int i = 0; i < M ; i++) {
        scanf("%d", &stairs[i]);
    }
    for (int i = 0; i < M; i++) {
        for (int j = i + 1; j <= i + K && j < M; j++) {
            if (stairs[j] <= ((long long)stairs[i]) + H && stairs[j] >= stairs[i] - H) {
                total++;
            }
        }
    }
    printf("%lld\n", total);
    return 0;
}