A_Changing_Volume.cpp

// Neepan Biswas
// neepanb ~ codeforces
#include <bits/stdc++.h>
using namespace std;

#define fr(i, n) for (lli i = 0; i < n; i++)
#define pb push_back
#define sz(x) x.size()
#define ff first
#define ss second
#define all(v) v.begin(), v.end()
#define debug(x) cout << '>' << #x << ':' << x << endl;
#define cd(condition, value_if_true, value_if_false) ((condition) ? (value_if_true) : (value_if_false))

using lli = long long int;
using ld = long double;
using pi = pair<lli, lli>;
using vp = vector<pi>;
using vi = vector<lli>;
using bl = bool;
using mp = map<lli, lli>;
using ump = unordered_map<lli, lli>;
using str = string;

#pragma GCC optimize("unroll-loops,O3,Ofast")
#pragma GCC target("avx2,avx,fma,bmi,bmi2,lzcnt,popcnt")

int main()
{
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    lli t;
    cin >> t;

    while (t--)
    {
        lli a, b;
        cin >> a >> b;

        lli diff = abs(b - a);
        lli presses = 0;

        presses += diff / 5;
        diff %= 5;

        presses += diff / 2;
        diff %= 2;

        presses += diff;

        cout << presses << endl;
    }

    return 0;
}