Judge Girl - 240. Square, Diamond, and Rectangle

240. Square, Diamond, and Rectangle.c

#include <stdio.h>
#include <stdbool.h>
#define SWAP(T, X, Y) \
    do { \
        T johnchen902_swap_temp = X; \
        X = Y; \
        Y = johnchen902_swap_temp; \
    } while(0)
int main() {
    int t;
    scanf("%d", &t);
    while(t--) {
        int x1, y1, x2, y2, x3, y3, x4, y4;
        scanf("%d %d %d %d %d %d %d %d", &x1, &y1, &x2, &y2, &x3, &y3, &x4, &y4);
        if(x1 + x2 == x3 + x4 && y1 + y2 == y3 + y4)
            ; // No swaps
        else if(x1 + x3 == x2 + x4 && y1 + y3 == y2 + y4) {
            SWAP(int, x2, x3);
            SWAP(int, y2, y3);
        } else if(x1 + x4 == x2 + x3 && y1 + y4 == y2 + y3) {
            SWAP(int, x2, x4);
            SWAP(int, y2, y4);
        } else {
            // not even a parallelogram
            puts("other");
            continue;
        }
        int dx1 = x1 - x2, dy1 = y1 - y2, dx2 = x3 - x4, dy2 = y3 - y4;
        bool is_diamond   = dx1 * dx2 + dy1 * dy2 == 0;
        bool is_rectangle = dx1 * dx1 + dy1 * dy1 == dx2 * dx2 + dy2 * dy2;
        if(is_diamond && is_rectangle)
            puts("square");
        else if(is_diamond)
            puts("diamond");
        else if(is_rectangle)
            puts("rectangle");
        else
            puts("other");
    }
}