A633.高精度A+B

#include<iostream>
#include<cstring>
using namespace std;
string add(string A,string B){
	string C="";
	int a[300],b[300],sum[301],c[301],lena=A.length(),lenb=B.length(),i=0,max=(lena>lenb?lena:lenb),x=0,digs=max;
	memset(a,0,sizeof(a));
	memset(b,0,sizeof(b));
	memset(sum,0,sizeof(c));
	for(;i<max;i++){
		if(i<lena) a[i]=A[lena-i-1]-'0';
		if(i<lenb) b[i]=B[lenb-i-1]-'0';
		sum[i]=a[i]+b[i]+x;
		x=sum[i]/10;
		sum[i]%=10;
	}
	digs+=x;
	if(x){
		sum[i]=a[i]+b[i]+x;
		x=sum[i]/10;
		sum[i]%=10;
	}
	for(int i=0;i<digs;i++){
		c[i]=sum[digs-i-1];
		C+=c[i]+'0';
	}
	return C;
}
int main(){
	string a,b;
    cin>>a>>b;
    cout<<add(a,b);
	return 0;
}