https://codeforces.com/problemset/problem/75/A

#include<bits/stdc++.h>
using namespace std;
int solve(string s)
{
	int sum=0;
	for(int i=0;i<s.size();i++) if(s[i]>'0') sum=sum*10+s[i]-'0';
	return sum;
}
int main(void)
{
	int a,b; cin>>a>>b;
	int c=a+b;
	string s1,s2,s3;
	s1=to_string(a);
	s2=to_string(b);
	s3=to_string(c);
	if(solve(s1)+solve(s2)==solve(s3))  puts("YES");
	else puts("NO");
}