HDU1030_Delta-wave_多维坐标

Delta-wave

Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)
Total Submission(s): 8610    Accepted Submission(s): 3428

Problem Description

A triangle field is numbered with successive integers in the way shown on the picture below. 



The traveller needs to go from the cell with number M to the cell with number N. The traveller is able to enter the cell through cell edges only, he can not travel from cell to cell through vertices. The number of edges the traveller passes makes the length of the traveller's route. 

Write the program to determine the length of the shortest route connecting cells with numbers N and M. 

 

Input

Input contains two integer numbers M and N in the range from 1 to 1000000000 separated with space(s).

 

Output

Output should contain the length of the shortest route.

 

Sample Input

6 12 

 

Sample Output

3

 

大致题意：

如图结构的一个地图，给出两个数字。求从第一个数字移动到第二个数字的最小步数。

大体思路：

可以把图中的每一个格用一个三维坐标表示。最后三维坐标的差值加起来即可。

#include<cstdio>#include<cmath>#include<cstdlib>int main(){int M,N,Mx,My,Mz,Nx,Ny,Nz;while(scanf("%d%d",&M,&N)!=EOF){Mx=sqrt(M-1)+1;My=(M-(Mx-1)*(Mx-1)+1)/2;Mz=(Mx*Mx-M)/2+1;Nx=sqrt(N-1)+1;Ny=(N-(Nx-1)*(Nx-1)+1)/2;Nz=(Nx*Nx-N)/2+1;printf("%d\n",abs(Mx-Nx)+abs(My-Ny)+abs(Mz-Nz));}return 0;}