这题只要注意9以上的数字的处理就行了。

上AC代码

#include<bits/stdc++.h>
using namespace std;
const int N=1e3+10;
long long n,a[N],b[N],c[N];
int main(){
#define int long long
	char s1[N],s2[N];
	cin>>n>>s1>>s2;
	int l=strlen(s1),r=strlen(s2);int s=max(l,r);
	for(int i=0;i<l;i++){
		if(s1[i]>='a'&&s1[i]<='z')a[l-i]=s1[i]-87;
		else a[l-i]=s1[i]-48;
	}
	for(int i=0;i<r;i++){
		if(s2[i]>='a'&&s2[i]<='z')b[r-i]=s2[i]-87;
		else b[r-i]=s2[i]-48;
	}
	for(int i=0;i<=s;i++){
		c[i]+=a[i]+b[i];
		c[i+1]+=c[i]/n;
		c[i]%=n;
	}
	if(c[s+1]){
		s++;
	}
	for(int i=s;i>0;i--){
		if(c[i]>9)cout<<char(c[i]+87);
		else cout<<c[i];
	}
	return 0;
}

点个赞吧，球球了。

#include <bits/stdc++.h>
using namespace std;
#define LL long long
const int N = 1e5 + 10;
const int INF = 0x3f3f3f3f;
int a[1005], b[1005], c[1005];
char s1[1005], s2[1005];
int main()
{
	int n;
	cin >> n >> s1 >> s2;
	int l = strlen(s1);
	for (int i = 0; i < l; i++)
		if (s1[i] >= 'a' && s1[i] <= 'z')
			a[l - i] = s1[i] - 87;
		else
			a[l - i] = s1[i] - 48;
	l = strlen(s2);
	for (int i = 0; i < l; i++)
		if (s2[i] >= 'a' && s2[i] <= 'z')
			b[l - i] = s2[i] - 87;
		else
			b[l - i] = s2[i] - 48;
	l = max(strlen(s1), strlen(s2));
	for (int i = 1; i <= l; i++)
	{
		c[i] += a[i] + b[i];
		c[i + 1] = c[i] / n;
		c[i] %= n;
	}
	if (c[l + 1])
		l++;
	for (int i = l; i > 0; i--)
		if (c[i] > 9)
			cout << char(c[i] + 87);
		else
			cout << c[i];
	return 0;
}

/*****************************************
备注：
******************************************/
#include <queue>
#include <math.h>
#include <stack>
#include <stdio.h>
#include <iostream>
#include <vector>
#include <iomanip>
#include <string.h>
#include <algorithm>
using namespace std;
#define LL long long
const int N = 1e5 + 10;
const int INF = 0x3f3f3f3f;
int a[1005], b[1005], c[1005];
char s1[1005], s2[1005];
int main()
{
	int n;
	cin >> n >> s1 >> s2;
	int l = strlen(s1);
	for (int i = 0; i < l; i++)
		if (s1[i] >= 'a' && s1[i] <= 'z')
			a[l - i] = s1[i] - 87;
		else
			a[l - i] = s1[i] - 48;
	l = strlen(s2);
	for (int i = 0; i < l; i++)
		if (s2[i] >= 'a' && s2[i] <= 'z')
			b[l - i] = s2[i] - 87;
		else
			b[l - i] = s2[i] - 48;
	l = max(strlen(s1), strlen(s2));
	for (int i = 1; i <= l; i++)
	{
		c[i] += a[i] + b[i];
		c[i + 1] = c[i] / n;
		c[i] %= n;
	}
	if (c[l + 1])
		l++;
	for (int i = l; i > 0; i--)
		if (c[i] > 9)
			cout << char(c[i] + 87);
		else
			cout << c[i];
	return 0;
}