这...感觉应该没毛病啊

求大佬指点一下

#include<iostream>
using namespace std;
const int N=22;
int a[N],b[N];
int p[N]={2,3,5,7,11,13,17,23};
/*
10,6,4,2,1+9,5,3,2,1
*/
void a_b_sum(int len1,int len2)
{
	int len=max(len1,len2);
	int sum[N]={0};
	int l=0,t=0;
	for(int i=len-1;i>=0;i--)
	{
		sum[l]=a[i]+b[i]+t;
		t=sum[l]/p[l];
		sum[l]%=p[l];
		l++;
	}
	if(t)
	sum[l++]=t;
	for(int i=l-1;i>=0;i--)
	if(i!=0)
	cout<<sum[i]<<",";
	else
	cout<<sum[i];
}
int main()
{
	string str;
	int sum=0;
	int len1=0,len2=0;
	cin>>str;
	int x=str.find("+");
	for(int i=0;i<x;i++)
	{
		if(str[i]!=',')
		{
			sum=sum*10+str[i]-'0';
		}
		else
		{
			a[len1++]=sum;
			sum=0;
		}
	}
	a[len1++]=sum;
	sum=0;
	for(int i=x+1;i<=str.length()-1;i++)
	{
		if(str[i]!=',')
		{
			sum=sum*10+str[i]-'0';
		}
		else
		{
			b[len2++]=sum;
			sum=0;
		}
	}
	b[len2++]=sum;
	a_b_sum(len1,len2);
	/*cout<<endl;
	for(int i=0;i<=max(len1,len2)-1;i++)
	cout<<p[i]<<" ";
	cout<<endl;
	for(int i=len1-1;i>=0;i--)
	cout<<a[i]<<" ";
	cout<<endl;
	for(int i=len2-1;i>=0;i--)
	cout<<b[i]<<" ";*/
	return 0;
}