Language: C++

#include<algorithm>
#include<queue>
#include<stdio.h>
#include<stdlib.h>
#include<vector>

using namespace std;

int main(void){
	long long K = 0, N = 0;
	unsigned __int64 x[55] = { 0 }, y[55] = { 0 };
	unsigned __int64 ans = INT_MAX;

	scanf("%lld%lld", &N, &K);
	for (int i = 0; i < N; i++){
		scanf("%lld %lld", &x[i], &y[i]);
	}

	for (int i = 0; i < N; i++){
		for (int j = 0; j < N; j++){
			unsigned __int64 a = 0;
			unsigned __int64 x1 = min(x[i], x[j]);
			unsigned __int64 x2 = max(x[i], x[j]);
			unsigned __int64 y1 = min(y[i], y[j]);
			unsigned __int64 y2 = max(y[i], y[j]);
			for (int k = 0; k < N; k++){
				if ((x1 <= x[k] && x[k] <= x2) && (y1 <= y[k] && y[k] <= y2))
					a++;
			}

			if (a >= K)
				ans = min(ans, (unsigned __int64)((x2 - x1) * (y2 - y1)));

		}
	}
	printf("%I64o\n", ans);
	return 0;
}

Compiler output:
a.cc: In function 'int main()':
a.cc:11:26: error: expected initializer before 'x'
   11 |         unsigned __int64 x[55] = { 0 }, y[55] = { 0 };
      |                          ^
a.cc:11:39: error: expected primary-expression before ',' token
   11 |         unsigned __int64 x[55] = { 0 }, y[55] = { 0 };
      |                                       ^
a.cc:11:41: error: 'y' was not declared in this scope
   11 |         unsigned __int64 x[55] = { 0 }, y[55] = { 0 };
      |                                         ^
a.cc:12:26: error: expected initializer before 'ans'
   12 |         unsigned __int64 ans = INT_MAX;
      |                          ^~~
a.cc:16:37: error: 'x' was not declared in this scope
   16 |                 scanf("%lld %lld", &x[i], &y[i]);
      |                                     ^
a.cc:21:42: error: expected initializer before 'a'
   21 |                         unsigned __int64 a = 0;
      |                                          ^
a.cc:22:42: error: expected initializer before 'x1'
   22 |                         unsigned __int64 x1 = min(x[i], x[j]);
      |                                          ^~
a.cc:23:42: error: expected initializer before 'x2'
   23 |                         unsigned __int64 x2 = max(x[i], x[j]);
      |                                          ^~
a.cc:24:42: error: expected initializer before 'y1'
   24 |                         unsigned __int64 y1 = min(y[i], y[j]);
      |                                          ^~
a.cc:25:42: error: expected initializer before 'y2'
   25 |                         unsigned __int64 y2 = max(y[i], y[j]);
      |                                          ^~
a.cc:27:38: error: 'x1' was not declared in this scope
   27 |                                 if ((x1 <= x[k] && x[k] <= x2) && (y1 <= y[k] && y[k] <= y2))
      |                                      ^~
a.cc:27:44: error: 'x' was not declared in this scope
   27 |                                 if ((x1 <= x[k] && x[k] <= x2) && (y1 <= y[k] && y[k] <= y2))
      |                                            ^
a.cc:27:60: error: 'x2' was not declared in this scope
   27 |                                 if ((x1 <= x[k] && x[k] <= x2) && (y1 <= y[k] && y[k] <= y2))
      |                                                            ^~
a.cc:27:68: error: 'y1' was not declared in this scope
   27 |                                 if ((x1 <= x[k] && x[k] <= x2) && (y1 <= y[k] && y[k] <= y2))
      |                                                                    ^~
a.cc:27:90: error: 'y2' was not declared in this scope
   27 |                                 if ((x1 <= x[k] && x[k] <= x2) && (y1 <= y[k] && y[k] <= y2))
      |                                                                                          ^~
a.cc:28:41: error: 'a' was not declared in this scope
   28 |                                         a++;
      |                                         ^
a.cc:31:29: error: 'a' was not declared in this scope
   31 |                         if (a >= K)
      |                             ^
a.cc:32:33: error: 'ans' was not declared in this scope; did you mean 'abs'?
   32 |                                 ans = min(ans, (unsigned __int64)((x2 - x1) * (y2 - y1)));
      |                                 ^~~
      |                                 abs
a.cc:32:49: error: expected primary-expression before 'unsigned'
   32 |                                 ans = min(ans, (unsigned __int64)((x2 - x1) * (y2 - y1)));
      |                                                 ^~~~~~~~
a.cc:32:49: error: expected ')' before 'unsigned'
   32 |                                 ans = min(ans, (unsigned __int64)((x2 - x1) * (y2 - y1)));
      |                                                ~^~~~~~~~
      |                                                 )
a.cc:36:27: error: 'ans' was not declared in this scope; did you mean 'abs'?
   36 |         printf("%I64o\n", ans);
      |                           ^~~
      |                           abs