V

#include <stdio.h>
int a[100010] = {0},s[100010] = {0};
int main(int argc,char **argv){
    int n,m,i,j,ans = -1;
    scanf("%d%d",&n,&m);
    if(n == 1){
        scanf("%d",&i);
        printf("%d\n",i == m);
    }
    else{
        for(i = 1;i <= n;i++){
            scanf("%d",a + i);
            s[i] = (s[i - 1] + a[i]) % m;
        }
        for(i = 1;i <= n;i++){
            for(j = i + 1;j <= n;j++){
                if((s[i] - s[j]) % m == 0){
                    if(j - i > ans)ans = j - i;
                }
            }
        }
        printf("%d\n",ans);
    }
    return 0;
}