uva - 516 - Prime Land

#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<vector>
#include<iostream>
#include<cmath>
using namespace std;
bool mark[33000];
int main()
{
    char a[10000];
    memset(mark,true,sizeof(mark));
    mark[0]=mark[1]=false;
    for(int i=4;i<=10000;i=i+2)mark[i]=false;
    for(int i=3;i*i<=10000;i=i+2)
    {
        if(mark[i])
        {
            for(int j=i*i;j<=10000;j=j+2*i ) mark [j] = false;
        }
    }
    vector<int>prime;
    for(int i=2;i<33000;i++)if(mark[i])prime.push_back(i);
    while(gets(a)!=NULL)
    {
        char *ch;
        ch=strtok(a," ");
        int i=atoi(ch);
        if(i==0)break;
        ch=strtok(NULL," ");
        int sum=0;
        sum=pow(i,atoi(ch));
        while(true)
        {
            ch=strtok(NULL," ");
            if(!ch)break;
            i=atoi(ch);
            ch=strtok(NULL," ");
            sum=sum*pow(i,atoi(ch));
        }
        sum=sum-1;
        int freq[33000];
        //printf("%d\n",sum);
        memset(freq,0,sizeof(freq));
        for(i=0;i<prime.size()&&sum>1;i++)
        {
            int n=prime[i];
            while(sum%n==0)
            {
                freq[n]++;
                sum=sum/n;
            }
        }
        bool flag=false;
        for(i=33000-1;i>=0;i--)
        {
            if(freq[i]>0)
            {
                if(flag==true)printf(" ");
                printf("%d %d",i,freq[i]);
                flag=true;
            }

        }printf("\n");
    }
    return 0;
}