poj 4006:小兔子捡金币

螺旋矩阵

#include<iostream>#include<cmath>using namespace std;int main(){int m,n;cin>>m>>n;while(m--){int p,q,r;cin>>p>>q;r = min(p-1,q-1);r = min(r,n-p);r = min(r,n-q);int s = 0;int t = n - 2 * r;p = p - r;q = q - r;for(int i=1;i<=r;i++)s += 4 * (n - 1 - 2 * (i - 1));if(p == 1){cout<<s + q<<endl;continue;}if(q == t){s += t - 1;s += p;cout<<s<<endl;continue;}if(p == t){s += 2 * (t-1);s += t - q + 1;cout<<s<<endl;continue;  }if(q == 1){s += 3 * (t - 1);s += t - p + 1;cout<<s<<endl;continue;}}return 0;}