做了50分钟

#include<bits/stdc++.h>
using namespace std;

int main()
{
    string a,b;
    cin >> a >> b;
    int ad=a.size(),bd=b.size(),carry=0,max;
    if (ad>bd)
    	max=ad;
    else if (ad<bd)
    	max=bd;
    else
    	max=ad;
    int aar[max],bar[max],ans[max+1];
    for (int i=0;i<max;i++)
    {
    	aar[i]=0;
    	bar[i]=0;
    	ans[i]=0;
	}
	ans[max]=0;
    for (int i=0;i<ad;i++)
        aar[i]=a[ad-i-1]-48;
    for (int i=0;i<bd;i++)
        bar[i]=b[bd-i-1]-48;
    for (int i=0;i<max;i++)
    {
        if (aar[i]+bar[i]>=10)
        {
            ans[i]=aar[i]+bar[i]-10+carry;
            carry=1;
            if (carry>1)
                carry=1;
        }
        else if (aar[i]+bar[i]<10)
        {
            if (aar[i]+bar[i]+carry==10)
            {
                ans[i]==0;
                carry=1;
            }
            else
            {
            	ans[i]=aar[i]+bar[i]+carry;
            	carry=0;
            }
        }
	}
    if (carry==1)
        ans[max]=1;
    if (carry==0)
    {
    	for (int i=max-1;i>=0;i--)
        	cout << ans[i];
    }
    else
    {
    	for (int i=max;i>=0;i--)
        	cout << ans[i];
    }
    
	return 0;
}