各位大佬看看有什么问题吗```
#include<stdio.h>
int main()
{
long long n = 0;
long long k = 0;
scanf("%d %d", &n,&k);
long long arr[1000000];
for (long long i = 0; i < n; i++)
{
scanf("%d ", &arr[i]);
}
if(k!=0)
arr[k - 1] -= arr[k - 1]*2;
else
arr[k]-=arr[k]*2;
long long x = 0;
for (long long j = 0; j < n; j++)
{
x = x + arr[j];
}
printf("%d", x);
return 0;
}
