One of Timofey's birthday presents is a colourbook in a shape of an infinite plane. On the plane n rectangles with sides parallel to coordinate axes are situated. All sides of the rectangles have odd length. Rectangles cannot intersect, but they can touch each other.
Help Timofey to color his rectangles in 4 different colors in such a way that every two rectangles touching each other by side would have different color, or determine that it is impossible.
Two rectangles intersect if their intersection has positive area. Two rectangles touch by sides if there is a pair of sides such that their intersection has non-zero length
The
picture corresponds to the first exampleThe first line contains single integer n (1 ≤ n ≤ 5·105) — the number of rectangles.
n lines follow. The i-th of these lines contains four integers x1, y1, x2 and y2 ( - 109 ≤ x1 < x2 ≤ 109, - 109 ≤ y1 < y2 ≤ 109), that means that points (x1, y1) and (x2, y2) are the coordinates of two opposite corners of the i-th rectangle.
It is guaranteed, that all sides of the rectangles have odd lengths and rectangles don't intersect each other.
Print "NO" in the only line if it is impossible to color the rectangles in 4 different colors in such a way that every two rectangles touching each other by side would have different color.
Otherwise, print "YES" in the first line. Then print n lines, in the i-th of them print single integer ci (1 ≤ ci ≤ 4) — the color of i-th rectangle.
8 0 0 5 3 2 -1 5 0 -3 -4 2 -1 -1 -1 2 0 -3 0 0 5 5 2 10 3 7 -3 10 2 4 -2 7 -1
YES 1 2 2 3 2 2 4 1
#include <bits/stdc++.h>
using namespace std;
int n;
int main(){
while(scanf("%d", &n) == 1){
printf("YES\n");
for(int i = 0; i < n; i++){
int x1, y1, x2, y2;
scanf("%d%d%d%d", &x1, &y1, &x2, &y2);
if(x2&1){
printf(y2&1 ? "3\n" : "1\n");
}
else{
printf(y2&1 ? "4\n" : "2\n");
}
}
}
}
本文探讨了一个基于平面直角坐标系的矩形染色问题,利用四色定理来解决如何使用四种不同颜色为矩形染色,确保相邻矩形颜色不同。通过分析矩形端点的颜色特性,提出了一种有效的染色方案。
6496

被折叠的 条评论
为什么被折叠?



