Sum of divisors（进制转换） HDU - 4432

mmm is learning division, she's so proud of herself that she can figure out the sum of all the divisors of numbers no larger than 100 within one day!
But her teacher said "What if I ask you to give not only the sum but the square-sums of all the divisors of numbers within hexadecimal number 100?" mmm get stuck and she's asking for your help.
Attention, because mmm has misunderstood teacher's words, you have to solve a problem that is a little bit different.
Here's the problem, given n, you are to calculate the square sums of the digits of all the divisors of n, under the base m.

InputMultiple test cases, each test cases is one line with two integers.
n and m.(n, m would be given in 10-based)
1≤n≤10 ⁹
2≤m≤16
There are less then 10 test cases.
OutputOutput the answer base m.

Sample Input

10 2
30 5

Sample Output

110
112

        
 

Hint

Use A, B, C...... for 10, 11, 12......
Test case 1: divisors are 1, 2, 5, 10 which means 1, 10, 101, 1010 under base 2, the square sum of digits is 
1^2+ (1^2 + 0^2) + (1^2 + 0^2 + 1^2) + .... = 6 = 110 under base 2.

题意：比较好理解

分析：二进制转换基本应用

AC代码：

#include<iostream>
#include<cstring>
#include<cstdio>
#include<algorithm>
using namespace std;
const int maxn = 1e5+10;
#define LL long long
#define INF 0x3f3f3f3f
LL n,m;
int pos=0;
int a[110];

LL trans(LL x){
    LL res=0;
    while(x){
        res+=(x%m)*(x%m);
        x/=m;
    }
    return res;
}

int main(){
    while(~scanf("%lld%lld",&n,&m)){
        LL ans=0;
        for(int i=1;i<=sqrt(n);i++){
            if(n%i==0){
                ans+=trans(i);
                if(i!=n/i) ans+=trans(n/i);
            }
        }
        pos=0;
        memset(a,0,sizeof(a));
        while(ans){
            a[pos++]=ans%m;
            ans/=m;
        }
        for(int i=pos-1;i>=0;i--){
            if(a[i]>=10) printf("%c",a[i]-10+'A');
            else printf("%d",a[i]);
        }
        printf("\n");
    }



    return 0;
}