Hdu 1496 Equations (brute force, hash table pruning)

Hdu 1496 Equations (brute force, hash table pruning)
EquationsTime Limit: 6000/3000 MS (Java/Others) Memory Limit: 32768/32768 K (Java/Others)Total Submission (s): 5630 Accepted Submission (s): 2237

Problem DescriptionConsider equations having the following form:

A * x1 ^ 2 + B * x2 ^ 2 + c * x3 ^ 2 + d * x4 ^ 2 = 0
A, B, c, d are integers from the interval [-50, 50] and any of them cannot be 0.

It is consider a solution a system (x1, x2, x3, x4) that verifies the equation, xi is an integer from [-100,100] and xi! = 0, any I ε {1, 2, 3, 4 }.

Determine how many solutions satisfy the given equation.

InputThe input consists of several test cases. Each test case consists of a single line containing the 4 coefficients a, B, c, d, separated by one or more blks.
End of file.
OutputFor each test case, output a single line containing the number of the solutions.

Sample Input

1 2 3 -41 1 1 1

Sample Output

390880

AuthorLL
Source "2006 campus cultural activity month"-"celebration Cup" College Students' Program Design Competition and the fourth college students' Program Design Competition code of Hangzhou University of electronic science and technology is as follows:

#include
 
  int main(){int a,b,c,d,i,j,k,count,l,s1,s2;int pow[110];while(~scanf("%d%d%d%d",&a,&b,&c,&d)){count=0;for(i=1;i<101;++i)pow[i]=i*i;if(a>0&&b>0&&c>0&&d>0||a<0&&b<0&&c<0&&d<0){printf("0\n");continue;}for(i=1;i<101;++i){for(j=1;j<101;++j){s1=a*pow[i]+b*pow[j];if(s1>0&&c>0&&d>0||s1<0&&c<0&&d<0)continue;for(k=1;k<101;++k){s2=s1+c*pow[k];if(s2%d==0){s2/=-d;if(s2>0){for(l=1;l<101;++l){if(s2==pow[l]){count++;break;}}}}}}}printf("%d\n",count*16);}return 0;}