Number Steps

Problem Description Starting from point (0,0) on a plane, we have written all non-negative integers 0, 1, 2,... as shown in the figure. For example, 1, 2, and 3 has been written at points (1,1), (2,0), and (3, 1) respectively and this pattern has continued. You are to write a program that reads the coordinates of a point (x, y), and writes the number (if any) that has been written at that point. (x, y) coordinates in the input are in the range 0...5000.   Input The first line of the input is N, the number of test cases for this problem. In each of the N following lines, there is x, and y representing the coordinates (x, y) of a point.   Output For each point in the input, write the number written at that point or write No Number if there is none.   Sample Input 3 4 2 6 6 3 4   Sample Output 6 12 No Number

题意：如图规律，查询每个点的值，没有值的点输出No Number。

找下规律就行了，输入的两个数是坐标，只有同为奇数或同为偶数才有值，而且横坐标等于纵坐标或者比纵坐标大二。偶数相加为两个之和，奇数相加则为和减一。

#include<stdio.h> int main() { int t,n,m; scanf("%d",&t); while(t--) { int j,i; scanf("%d%d",&n,&m); j=n%2+m%2; i=n-m; if(i>=0&&i<=2&&j!=1) { if(j==0) printf("%d\n",n+m); if(j==2) printf("%d\n",n+m-1); } else printf("No Number\n"); } return 0; }