- 题目描述：
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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.
- 输入：
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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.
- 输出：
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For each point in the input, write the number written at that point or write No Number if there is none.
- 样例输入：
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3 4 2 6 6 3 4
- 样例输出：
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6 12 No Number
#include<iostream> using namespace std; int change(int x,int y){ if(x==0 && y==0) return 0; else if(x==1 && y==1) return 1; else if(x%2==0 && y==x-2) return x+y; else if(x%2==0 && y==x) return x+y; else if(x%2==1 && y==x-2) return x+y-1; else if(x%2==1 && y==x) return x+y-1; else return -1; } int main(){ int n; while(cin>>n){ for(int i=0;i<n;i++){ int x,y; cin>>x>>y; int c=change(x,y); if(c==-1) cout<<"No Number"<<endl; else cout<<c<<endl; } } return 0; }