HDU2058：The sum problem

Problem Description

Given a sequence 1,2,3,......N, your job is to calculate all the possible sub-sequences that the sum of the sub-sequence is M.

 

 

Input

Input contains multiple test cases. each case contains two integers N, M( 1 <= N, M <= 1000000000).input ends with N = M = 0.

 

 

Output

For each test case, print all the possible sub-sequence that its sum is M.The format is show in the sample below.print a blank line after each test case.

 

 

Sample Input

20 10 50 30 0 0

 

 

Sample Output

[1,4] [10,10] [4,8] [6,9] [9,11] [30,30]

 

 

#include <string.h>

#include <stdio.h>

#include <math.h>



int main()

{

    int i,j,n,m,t;

   while(scanf("%d%d",&n,&m), m && n)

   {

           m*=2;

           for(i=(int)sqrt((double)m);i>=2;i--)

           {

                 if(m%i==0)

                 {

                         t=m/i+1-i;

                         if (t>=2 && t%2==0)

                         {

                              t>>=1;

                              if(t+i-1<=n)

                                  printf("[%d,%d]\n",t,t+i-1);

                          }

                 }

           }

           m>>=1;

           if(n>=m) printf("[%d,%d]\n",m,m);

           printf("\n");

    }

   return 0;

}