题解 | #Number Steps#

#include <iostream>

using namespace std;

const int N = 5010;
int a[N][N];
int dx[] = {1, 1, 1, -1}, dy[] = {1, -1, 1, 1};
int main() {
    //预处理
    int k = 1;
    int sx=0,sy=0;
    for(int i=0;i<=10000;i++){
        sx=sx+dx[i%4];
        sy=sy+dy[i%4];
        a[sx][sy]=k;
        k++;
    }
    int x,y;
    while (cin >> x >> y) {
        if (a[x][y]) cout << a[x][y] << endl;
        else cout << "No Number" << endl;
    }
    return 0;
}