Codeforces Round #601 (Div. 2), problem: (A) Changing Volume

#include<bits/stdc++.h>
using namespace std;
int main()
{
    int t;
    cin>>t;
    while(t--)
    {
        int a,b;
        cin>>a>>b;
        if(b>a) swap(a,b);
        a = a-b;
        int cnt = a/5;
        a %= 5;
        cnt += a/2;
        a %= 2;
        if(a>0) cout<<cnt+1<<endl;
        else cout<<cnt<<endl;
    }
return 0;
}