60，4*WA

#include <bits/stdc++.h>
using namespace std;
string a,b;
int c[10088],d[10088],e[10088];
int main(){
	cin>>a>>b;
	for(int i = 0;i<a.size();i++)c[i+1] = a[a.size()-i+-1]-'0';
	for(int i = 0;i<b.size();i++)d[i+1] = b[b.size()-i-1]-'0';
	if(a.size()<b.size() || (a.size() == b.size() && a<b)){
		swap(a,b);
		printf("-");
	}
	for(int i = 1;i<=max(a.size(),b.size());i++){
		if(c[i]<d[i]){
			c[i]+=10;
			c[i+1]--;
		}
		e[i] = c[i]-d[i];
	}
	int len = max(a.size(),b.size());
	while(!e[len] && len>1)len--;
	for(int i = len;i>=1;i--)cout<<e[i];
	return 0;
}