#include<stdio.h> int main() { int x, y = 0; int x1, y1 = 0; scanf("%d%d%d%d", &x, &y, &x1, &y1); if (x1 - x == 0 && y1 - y == 1) { printf("u\n"); } else if (x1 - x == 0 && y1 - y == -1) { printf("d\n"); } else ...