西南交大公開賽 Not So Flat After All（合數分解）

給出2個數，找出素因子分解的形式，給出2數素因子集合并集的基數，以及對應指數的絕對值之和

#include <cstdio>#include <cstring>#define abs(a) (a)>(0)?(a):(-(a))const int maxn=1000000;const int PRIMERANGE = 1000000;int prime[PRIMERANGE + 1];int getPrime(){    memset (prime, 0, sizeof (int) * (PRIMERANGE + 1));    for (int i = 2; i <= PRIMERANGE; i++)    {        if (!prime[i]) prime[++prime[0]] = i;        for (int j = 1; j <= prime[0] && prime[j] <= PRIMERANGE / i; j++)        {            prime[prime[j]*i] = 1;            if (i % prime[j] == 0) break;        }    }    return prime[0];}int factor[100][3], facCnt;int factor2[100][3];//only for this int getFactors(int x){    facCnt = 0;    memset(factor,0,sizeof(factor));    int tmp = x;    for(int i = 1; prime[i] <= tmp / prime[i]; i++)    {        factor[facCnt][1] = 1, factor[facCnt][2] = 0;        if(tmp % prime[i] == 0)            factor[facCnt][0] = prime[i];        while(tmp % prime[i] == 0)            factor[facCnt][2]++, factor[facCnt][1] *= prime[i], tmp /= prime[i];        if(factor[facCnt][1] > 1) facCnt++;    }    if(tmp != 1)        factor[facCnt][0] = tmp, factor[facCnt][1] = tmp, factor[facCnt++][2] = 1;    return facCnt;}int ans,cntans;int I=0;int main (){    getPrime();    int n,m;    while (scanf("%d%d",&n,&m),(n||m))    {        int cntn=getFactors(n);        memcpy(factor2,factor,sizeof(factor));        int cntm=getFactors(m);        int pn=0,pm=0;        ans=cntans=0;        while (pn<cntn && pm<cntm)        {            if(factor2[pn][0]<factor[pm][0]){ans++;cntans+=factor2[pn][2];  pn++;}            else            if(factor[pm][0]<factor2[pn][0]){ans++;cntans+=factor[pm][2]; pm++;}            else            {ans++ ; cntans+=abs(factor[pm][2]-factor2[pn][2]);pn++; pm++;}        }        ans+=(cntn-pn+cntm-pm);        while (pn<cntn)            cntans+=factor2[pn++][2];        while (pm<cntm)            cntans+=factor[pm++][2];        printf("%d. %d:%d\n",++I,ans,cntans);    }    return 0;}