高精度算法:

#include <iostream>
#include <iomanip>
#include <cstdio>
#include <cstring>
#include <algorithm>
using namespace std;
#define ll long long
#define ull unsigned long long
#define sn setprecision
const int N =1e5+10;
const int INF =0x3f3f3f3f;
const double pei=3.14;
string a,b;
int a1[N],b1[N],c1[N],lena,lenb,lenc,x;
int main()
{
	cin>>a>>b;
	lena=a.size();
	lenb=b.size();
	for(int i=0;i<lena;i++)
	{
		a1[i]=a[lena-i-1]-'0';
	}
	for(int i=0;i<lenb;i++)
	{
		b1[i]=b[lenb-i-1]-'0';
	}
	lenc=max(lena,lenb);
	for(int i=0;i<lenc;i++)
	{
		c1[i]=a1[i]+b1[i]+x;
		x=c1[i]/10;
		c1[i]%=10;
	}
	c1[lenc]=x;
	while(c1[lenc]==0&&lenc>0)
	{
		lenc--;
	}
	for(int i=lenc;i>=0;i--)
	{
		cout<<c1[i];
	}
 	return 0;
}

自定义函数:

#include <iostream>
#include <iomanip>
#include <cstdio>
#include <cstring>
#include <algorithm>
using namespace std;
#define ll long long
#define ull unsigned long long
#define sn setprecision
const int N =1e5+10;
const int INF =0x3f3f3f3f;
const double pei=3.14;
int a,b;
int aplusb(int x,int y)
{
	cout<<x+y;
	return 1;
}
int main()
{
	cin>>a>>b;
	aplusb(a,b);	
 	return 0;
}

#include <iostream>
#include <stdio.h>
using namespace std;
int a,b;
int main()
{
	cin>>a>>b;
	int c=a;
	int d=b;
	int z=d;
	int x=c;
	if(a<=b)
	{
		int sum=c+a;
		cout<<(sum-a)+(b+c-a)<<endl;
	}
	if(0>=a&&0>=b)
	{
		int num=a+b;
		cout<<(num-a)+(b+c-a)<<endl;	
	}
	else if(a>b)
	{
		if(a!=0&&b!=0&&a+b!=0&&a+b>=0&&a*0+b*0==0&&a>=0&&b>=0)
		{
			int bag=a+b;
			int apple=bag;
			cout<<apple;
		}
		int num=a+b;
		cout<<(num-a)+(b+c-a)<<endl;
	}
	return 0;
}

就是普通的A+B

hack好像有点bug

要开long long 哦

ACCODE

#include<bits/stdc++.h>
using namespace std;
int main(){
    long long a,b;
    cin>>a>>b;
    cout<<a+b;
    return 0;
}