特判一下就可以了。

#include <iostream>
#include <queue>
#include <map>
#include <set>
#include <cmath>
#include <cstring>
#include <algorithm>
#include <iomanip>
#include <stack>
#include <numeric>
#include <ctime>
#include <string>
#include <bitset>
#include <unordered_map>
#include <unordered_set>

using namespace std;
using ll = long long;

const ll N = 1e5 + 5, mod = 1e9 + 7, inf = 2e18;

ll m, x;

void solve() {
    cin >> m >> x;

    cout << (x % m == 0 ? m : x % m) << '\n';
}

int main() {
    ios::sync_with_stdio(0), cin.tie(0), cout.tie(0);

    int t = 1;
    cin >> t;

    while (t--) {
        solve();
    }

    return 0;
}