合数分解

 

const int maxn=30000+5;

int prime[maxn];
void marktable(int n){
    memset(prime,0,sizeof(prime));
    for(int i=2;i<=n;i++){
        if(!prime[i]) prime[++prime[0]]=i;
        for(int j=1;j<=prime[0]&&prime[j]<=n/i;j++){
            prime[prime[j]*i]=1;
            if(i%prime[j]==0) break;
        }
    }
}
long long factor[100][2];
int fatCnt;
int getFactors(long long x){
    fatCnt=0;
    long long tmp=x;
    for(int i=1;prime[i]<=tmp/prime[i];i++){
        factor[fatCnt][1]=0;
        if(tmp%prime[i]==0){
            factor[fatCnt][0]=prime[i];
            while(tmp%prime[i]==0){
                factor[fatCnt][1]++;
                tmp/=prime[i];
            }
            fatCnt++;
        }
    }
    if(tmp!=1) {
        factor[fatCnt][0]=tmp;
        factor[fatCnt++][1]=1;
    }
    return fatCnt;
}