poj 3844 Divisible Subsequences

poj 3844 Divisible Subsequences

#include<stdio.h>  #include<string.h>  int f[1000005];  __int64 ans;  int main()  {      int i,j,k,t,n,d;      scanf("%d",&t);      while(t--){          scanf("%d%d",&d,&n);          memset(f,0,sizeof(f));          int num=0; ans=0;          while(n--){   scanf("%d",&k);   num=(num+k)%d;   if(num==0) f[num]++;   ans+=f[num];   if(num!=0) f[num]++;          }          printf("%I64dn",ans);      }      return 0;  }