poj 1870 Bee Breeding
思路：首先要建立坐标，具体作法见：http://www.cnblogs.com/xin-hua/p/3237096.html
然后将得到2坐标之差x,y；如果x,y同号，则相加，否则去最大.(要取绝对值的)
代码如下：
1 #include<iostream> 2 #include<stdio.h> 3 #include<algorithm> 4 #include<iomanip> 5 #include<cmath> 6 #include<cstring> 7 #include<vector> 8 #define ll __int64 9 #define pi acos(-1.0) 10 #define MAX 50000 11 using namespace std; 12 struct dir 13 { 14 int x,y; 15 dir(){} 16 dir(int a,int b){ 17 x=a; 18 y=b; 19 } 20 dir operator+(dir A){ 21 return dir(A.x+x,A.y+y); 22 } 23 }an[6]; 24 dir solve(int n) 25 { 26 int k,m,i,j; 27 dir p; 28 k=((sqrt(12.0*n-3.0)-3.0)/6.0); 29 if(3*k*(k+1)+1!=n) k++; 30 p.x=k;p.y=0; 31 m=0; 32 if(k>0) m=6*k-((3*k*(k+1)+1)-n); 33 i=0; 34 while(m){ 35 for(j=0;j<k;j++){ 36 p=p+an[i]; 37 m--; 38 if(m==0) 39 break; 40 } 41 i++; 42 } 43 return p; 44 } 45 int main(){ 46 int n,x,y,ans,m; 47 an[0]=dir(-1,1);an[1]=dir(-1,0);an[2]=dir(0,-1); 48 an[3]=dir(1,-1);an[4]=dir(1,0);an[5]=dir(0,1); 49 while(cin>>n>>m){ 50 if(m==0&&n==0) break; 51 dir aa=solve(n); 52 dir bb=solve(m); 53 x=aa.x-bb.x; 54 y=aa.y-bb.y; 55 if((x<0&&y<0)||(x>0&&y>0)) 56 ans=abs(x+y); 57 else ans=max(abs(x),abs(y)); 58 printf("The distance between cells %d and %d is %d.\n",n,m,ans); 59 } 60 return 0; 61 }
