// Skyqwq
#include <bits/stdc++.h>

#define pb push_back
#define fi first
#define se second
#define mp make_pair

using namespace std;

typedef long long LL;

template <typename T> void chkMax(T &x, T y) { if (y > x) x = y; }
template <typename T> void chkMin(T &x, T y) { if (y < x) x = y; }

template <typename T> void inline read(T &x) {
    int f = 1; x = 0; char s = getchar();
    while (s < '0' || s > '9') { if (s == '-') f = -1; s = getchar(); }
    while (s <= '9' && s >= '0') x = x * 10 + (s ^ 48), s = getchar();
    x *= f;
}

int n, m, x1, x2;
 
int main() {
    int T; read(T);
    while (T--) {
        read(n), read(m), read(x1), read(x2);
        int ans = min(x1 - 1, m - x2);
        if (x1 != x2) chkMin(ans, max((n - 1 + abs(x1 - x2) - 1) / 2, 0));
        if (x1 == x2) chkMin(ans, (n - 1) / 2);
        chkMin(ans, n - 1);
        printf("%lld\n", 1ll * ans * ans);
    }
    return 0;
}