@各位大佬

long long n, c, t = 0;


scanf("%d %d", &n, &c);


for (int i = 1; i <= n; i++) cin >> b[i];


for (int i = 1; i <= n; i++) {


    for (int j = 2; j <= n; j++) {


        if (b[j] - b[i] == c)


            t++;


    }


}


printf("%d", t);


return 0;