#include<bits/stdc++.h>
using namespace std;
string fanzhuan(string str){
	string temp;
	for(int t = str.size() - 1;t >= 0;t--){
		temp.push_back(str[t]);
	}
	//cout << "[Info]main.fanzhuan:" << str << "->" << temp << endl;
	return temp;
}
char i2c(int num){
	return char(num + '0');
}
char c2i(char num){
	return int(num) - '0';
}
string more0(string num,int n){
	if(num == "0" || n == 0){
		return num;
	}
	for(int t = 0;t < n;t++){
		num += '0';
	}
	return num;
}
string add(string an,string bn){
	string a = an.size() > bn.size()?fanzhuan(an):fanzhuan(bn);
	string b = an.size() <= bn.size()?fanzhuan(an):fanzhuan(bn);
	
	bool next_bit = false;
	string sum;
	for(int t = 0;t < a.size();t++){
		char at = a[t];
		char bt = t < b.size()?b[t]:'0';
		//cout << "[I]" << at << "+" << bt << "=";
		next_bit = bool((c2i(at) + c2i(bt) + int(next_bit)) / 10);
		//cout << "[Info]main.add:计算结果=" << c2i(at) + c2i(bt) + int(next_bit) << endl;
		char thisbit = i2c((c2i(at) + c2i(bt) + int(next_bit)) % 10);
		//cout << "[Info]main.add:求余结果=" << thisbit << endl;
		//cout << thisbit << endl;
		sum.push_back(thisbit); 
	}
	if(next_bit){
		sum.push_back('1');
	}
	//cout << "[Info]main.add: a = " << a << ",b = " << b << ",re = " << fanzhuan(sum);
	return fanzhuan(sum);
}
string nCs(int num,string b){
	//cout << "[Info]" << num << " * " << b << "=";
	string sum = "0";
	int next_bit = 0;
	/*if(num == 0 || b == "0"){
		return "0";
	}*/
	string tempb = fanzhuan(b);
	cout << "[Info]main.nCs:tempb = " << tempb << endl;
	for(int t = 0;t < b.size();t++){
		/*if(tempb[t] == '0'){
			continue;
		}*/
		int result = next_bit + num * c2i(tempb[t]);
		next_bit = result / 10;
		result %= 10;
		string tt;
		tt.push_back(i2c(result));
		sum = add(sum,more0(tt ,t));
	}
	if(next_bit != 0){
		string tt;
		tt.push_back(i2c(next_bit));
		sum = add(sum,more0(tt,sum.size()));
	}
	//cout << sum << endl;
	return sum;
}
string nCn(string a,string b){
	//bool map[10] = {false};
	//string example[10] = {"0"};
	//b = fanzhuan(b);
	string sum = "0";
	/*if(a == "0" || b == "0"){
		return "0";
	}*/
	for(int t = 0;t < a.size();t++){
		char at = a[t];
		//string temp = ;
		cout << "[Info]main.nCn:nCs=" << more0(nCs(c2i(at),b),t) << endl; 
		//temp = more0(temp,t);
		sum = add(more0(nCs(c2i(at),b),t),sum);
	}
	return sum;
}
int main(void){
	//freopen("./a.in","r",stdin);
	string a,b;
	cin >> a >> b;
	if(a.size() > b.size()){
		string temp = b;
		b = a;
		a = temp;
	}
	int zsum = 0;
	string ta = fanzhuan(a);
	string tb = fanzhuan(b);
	int t;
	for(t = 0;t < ta.size();t++){
		if(ta[t] != '0'){
			break;
		}
		zsum++;
	}
	a = "";
	for(int i = t;i <ta.size();i++){
		a.push_back(ta[i]);
	}
	for(t = 0;t < tb.size();t++){
		if(tb[t] != '0'){
			break;
		}
		zsum++;
	}
	b = "";
	for(int i = t;i <tb.size();i++){
		b.push_back(tb[i]);
	}
	a = fanzhuan(a);
	b = fanzhuan(b);
	//cout << a << endl << b << endl;
	cout << more0(nCn(a,b),zsum);
	return 0;
}

求更正，错误数据： 123 321 此时会出错