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#include <iostream>
#include <cmath>
#include <cstdio>
#include <string>
#include <cstring>
#include <algorithm>
using std::string;
using namespace std;

int main(){
    char a[41] = {};
    char b[41] = {};
    int na, nb, M;
    
    cin.getline(a, 41, ' ');  
    cin.getline(b, 41);

    na = strlen(a);
    nb = strlen(b);
    M = na + nb;
    int ans[M] = {};
    int mul, sum;
    for(int i = na-1; i >= 0; --i){
        for(int j = nb-1; j >= 0; --j){
            mul = (a[i]-'0')*(b[j]-'0');
            sum = mul + ans[i+j+1];
            ans[i+j] += sum/10;
            ans[i+j+1] = sum % 10;
        }
    }
    
    int start = 0;
    while (start < M && ans[start] == 0) {
        start++;
    }
    
    if (start == M) {
        cout << "0";
    } else {
        for (int i = start; i < M; i++) {
            cout << ans[i];
        }
    }
    return 0;
}