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#include <stdlib.h>
#include <stdio.h>
int cmp(const void *x, const void *y)
{
return *(long long *) x - *(long long *) y;
}
int main()
{
short n, i;
long b;
scanf("%hd %ld", &n, &b);
long long *s = malloc(n * 8);
for (i = 0; i < n; i++)
scanf("%lld", &s[i]);
qsort(s, n, 8, cmp);
short m = 0, hist[10000] = {1};
long long a[10000];
a[0] = s[0];
for (i = 1; i < n; i++) {
if (s[i] != a[m]) {
m++;
a[m] = s[i];
}
hist[m]++;
}
m++;
long val = 0;
long long foo;
void *p;
for (i = 0; i < m; i++) {
foo = b - a[i];
if (foo == a[i])
val += hist[i] * (hist[i] - 1) / 2;
if (foo <= a[i])
break;
p = bsearch(&foo, a, m, 8, cmp);
if (p != NULL)
val += hist[i] * hist[(long long *) p - a];
}
printf("%ld\n", val);
return 0;
}
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