OJ Board

i used the following heuristic to solve the problem:
find the node with minimum degree put it in the solution vector and delete it and all the nodes connected to it and so on till u finish all the nodes.
it generates the right answer for the test cases so can any body points out what is wrong with ...

[cpp]
int Prime(int n, int alpha)
// Returns 1 if n is a prime and 0 otherwise.
// alpha is the probability parameter.
{
int q = n-1;
for (int i=1; i<=(alpha*log(n)); i++) {
int m = q, y = 1;
int a = random() % q + 1;
// Choose a random number in the range [1, n-1].
int z = a;
// Compute ...

i solved the problem and got it accepted and after rejudging i got time limit exceeded. here is the code
[cpp]
#include<iostream>
#include<cmath>
#include<fstream>
using namespace std;

int powerl(int,int);
bool primetest(int n);
int main()
{
//ofstream outs;
ifstream ins;
//outs.open("in.txt ...