#include <cstdio>
int m,n;
int num[25]={};
int c=0;

void f(int i, int s)
{
    if(i==n)
    {
        if(s==m)
            c++;
        return;
    }
    f(i+1,s+num[i]);
    f(i+1,s-num[i]);
}

int main()
{
    scanf("%d %d",&m,&n);
    for(int i=0; i<n; i++)
        {
         scanf("%d",&num[i]);
        }
    f(0,0);
    printf("%d",c);
    return 0;
}

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