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#include <iostream>

using namespace std;

string multiply_two_numbers_as_string(string a, string b) {
    int len_a = a.size();
    int len_b = b.size();
    int mult[len_a + len_b + 1];
    for(int i = 0; i < len_a + len_b + 1; i++) {
        mult[i] = 0;
    }
    int till_a = 0, till_b = 0;
    if(a[0] == '-') {
        till_a = 1;
    }
    if(b[0] == '-') {
        till_b = 1;
    }
    for(int i = len_a - 1; i >= till_a; i--) {
        for(int j = len_b - 1; j >= till_b; j--) {
            mult[i + j + 1] += (a[i] - '0') * (b[j] - '0');
        }
    }
    for(int i = len_a + len_b - 1; i >= 0; i--) {
        if(mult[i] > 9) {
            mult[i - 1] += (mult[i] / 10);
            mult[i] %= 10;
        }
    }
    int i = 0;
    while(mult[i] == 0) {
        i++;
    }
    string product = "";
    if(till_a != till_b) {
        product += "-";
    }
    for(int j = i; j < len_a + len_b; j++) {
        product += (mult[j] + '0');
    }
    return product;
}
int main() {
    string a, b;
    cin  >> a >> b;
    cout << multiply_two_numbers_as_string(a, b) << endl;
    return 0;
}