/**
 *    author: 小飞侠cy
 *    created: 2025.06.12 15:02:49
 */
#include <bits/stdc++.h>
using namespace std;
#define ls u << 1
#define rs u << 1 | 1
#define LL long long
//#define int long long
#define PII pair <int, int>
#define fi first
#define se second
#define pub push_back
#define pob pop_back
#define puf push_front
#define pof pop_front
#define lb lower_bound
#define ub upper_bound
#define i128 __int128
#define pcnt(x) __builtin_popcount(x)
#define mem(a,goal) memset(a, (goal), sizeof(a))
#define rep(x,start,end) for(int x = (start) - ((start) > (end)); x != (end) - ((start) > (end)); ((start) < (end) ? x ++ : x --))
#define aLL(x) (x).begin(), (x).end()
#define sz(x) (int)(x).size()
const int INF = 998244353;
const int mod = 1e9 + 7;
const int N = 100010;
void solve()
{
    int a, b, c, d;
    scanf("%d%d%d%d", &a, &b, &c, &d);
    int dx = abs(c - a);
    int dy = abs(d - b);
    if(dx == 0 && dy == 0)
    {
        cout << 0 << '\n';
        return ;
    }
    if(dy == 0)
    {
        if(dx <= 2) cout << 2 << '\n';
        else cout << (dx + 1) / 2 << '\n';
        return ;
    }

    int c1 = (dx + 1) / 2;
    int c2 = (dy + 1) / 2;
    cout << max(c1, c2) << '\n';
}
signed main()
{
    int t = 1;
    cin >> t;
    while (t --) solve();
    return 0;
}