#include<iostream> using namespace std; #define MAX 100 int fun(int* a,int length,int p=5) { int i,j,k; int time,sum=0; for(i=length;i>0;i--) { time=length-i+1; for(j=0;j<time;j++) { for(k=j;k<i+j;k++) sum=sum+a[k]; if(sum%p==0) return i; sum=0; } } return -1; } void main() { int a[MAX]; int N,i=0; while(cin>>N) a[i++]=N; cout<<fun(a,i)<<endl; }