#include <bits/stdc++.h>
using namespace std;

typedef long long ll;
int t, n, m, x1, x2, ans;

int read() {
    int x = 0, p = 1;
    char c = getchar();
    for (; !isdigit(c); c = getchar())
        if (c == '-') p = -1;
    for (; isdigit(c); c = getchar())
        x = (x << 3) + (x << 1) + (c & 15);
    return x * p;
}

void write(ll x) {
    if (x >= 10) write(x / 10);
    putchar(x % 10 + '0');
}

void writeln(ll x) {
    if (x < 0) {
        putchar('-');
        x = -x;
    }
    write(x);
    putchar('\n');
}

int main() {
    t = read();
    while (t--) {
        n = read();
        m = read();
        x1 = read();
        x2 = read();
        ans = min(n - 1, min(x1 - 1, m - x2));
        if (x1 < x2) ans = min(ans, (x2 + n - x1 - 2) / 2);
        if (x1 > x2) ans = min(ans, (n - x2 + x1 - 2) / 2);
        if (x1 == x2) ans = min(ans, (n - 1) / 2);
        writeln(1LL * ans * ans);
    }
    return 0;
}