#include <stdio.h>
#include <stdlib.h>

double getY(double m, int x, int in[]){
    return ((m*x)+(in[1]-(m*in[0])));
}

double getX(double m, int y, int in[]){
    return ((y-(in[1]-(m*in[0])))/m);
}

int countbox(int in[]){
printf("here");
    int i, x1, x2, y1, y2, count = 0;
    double m;
    x1 = in[0];
    y1 = in[1];
    x2 = in[2];
    y2 = in[3];
    m = ((y2-y1)/(x2-x1));

    i = 1;
    if(x1 < x2){
        while((x1+i)<x2){
            if(getY(m, (x1+i), in) != (double)(x1+i))
                count++;
        }
    }
    else if(x1 > x2){
        while((x1-i)>x2){
            if(getY(m, (x1-i), in) != (double)(x1-i))
                count++;
        }
    }
    i = 1;
    if(y1 < y2){
        while((y1+i)<y2){
            if(getX(m, (y1+i), in) != (double)(y1+i))
                count++;
        }
    }
    else if(y1 > y2){
        while((y1-i)>y2){
            if(getX(m, (y1-i), in) != (double)(y1-i))
                count++;
        }
    }
    return count;
}

int main(){
    int *res, in[4], i, j, n;
    j = 0;
    scanf("%d", &n);
    res = malloc(n*(sizeof(int)));
    for(i=0; i<n; i++)
    {
        scanf("%d", &in[0]);
        scanf("%d", &in[1]);
        scanf("%d", &in[2]);
        scanf("%d", &in[3]);
        res[j] = countbox(in);
        j++;
    }
    for(i=0; i<n; i++)
        printf("%d\n", res[i]);
    return 0;
}