高精度VS低精度

//高精度
#include<bits/stdc++.h>
#define int long long //int->long long
using namespace std;
bool hf(const string &a,const string &b){
    if(a.size()!=b.size())return a.size()<b.size();
    for(int i=0;i<a.size();i++){
        if(a[i]!=b[i])return a[i]<b[i];
    }
    return true;
}
signed main(){//int被变成long long，替换方案
	string a,b;
	cin>>a>>b;
	string x="",y="";
	for(int i=a.size()-1;i>=0;i--)x+=a[i];
	for(int i=b.size()-1;i>=0;i--)y+=b[i];
	int len,k=0,e=1;
	if(x.size()>y.size()){
        len=x.size();
        while(y.size()<x.size())y+="0";
    }else if(y.size()>x.size()){
        len=y.size();
        while(x.size()<y.size())x+="0";
        e=-1;
    }else{
        len=x.size();
        if(hf(a,b))e=-1;
    }
	if(e==-1)swap(x,y);//#include<algorithm>
	vector<char>c;//#include<vector>
	for(int i=0;i<len;i++){
		int diff=(x[i]-'0')-(y[i]-'0')-k;
		if(diff<0){
			c.push_back(diff+10+'0');
			k=1;
		}else{
			c.push_back(diff+'0');
			k=0;
		}
	}
	while(c.size()>1&&c.at(c.size()-1)=='0')c.pop_back();
    if(e==-1)c.push_back('-');
	for(int i=c.size()-1;i>=0;i--)cout<<c[i];
	return 0;
}

//低精度
#include<iostream>
using namespace std;
int main(){
    short a,b;//约32000
    cin>>a>>b;
    cout<<a-b;
    return 0;
}