A TIMES B!

#include <iostream>
#include <vector>
using namespace std;

int main()
{
    string a, b;
    cin >> a >> b;
    int k = a.size();
    int m = b.size();
    int n = k + m - 1;
    int s = 0;
    vector<int> res(n);
    for (int i = 0; i < n; i++) {
        s = 0;
        for (int j = max(0, i - m); j < i + 1; j++) {
            if (j < k && i - j < m) {
                s += (a[j] - '0') * (b[i - j] - '0');
            }
            res[i] = s;
        }
    }
    int c = 0;
    for (int i = n - 1; i >= 0; i--) {
        res[i] = res[i] + c;
        c = res[i] / 10;
        res[i] = res[i] % 10;
    }
    if (c != 0) {
        cout << c;
    }
    for (int i = 0; i < n; i++) {
        cout << res[i];
    }
    cout << endl;
    return 0;
}

Test 1

Verdict: ACCEPTED

Test 2

Verdict: ACCEPTED

Test 3

Verdict: ACCEPTED

Test 4

Verdict: ACCEPTED

Test 5

Verdict: ACCEPTED

Test 6

Verdict: ACCEPTED

Test 7

Verdict: ACCEPTED

Test 8

Verdict: ACCEPTED

Test 9

Verdict: ACCEPTED

Test 10

Verdict: ACCEPTED

Test 11

Verdict: ACCEPTED

Test 12

Verdict: ACCEPTED

Test 13

Verdict: ACCEPTED

Test 14

Verdict: ACCEPTED

Test 15

Verdict: ACCEPTED

Test 16

Verdict: ACCEPTED

Test 17

Verdict: ACCEPTED

Test 18

Verdict: ACCEPTED

Test 19

Verdict: ACCEPTED

Test 20

Verdict: ACCEPTED

Test 21

Verdict: ACCEPTED

Test 22

Verdict: ACCEPTED

Test 23

Verdict: ACCEPTED

Test 24

Verdict: ACCEPTED

Test 25

Verdict: ACCEPTED

Test 26

Verdict: ACCEPTED

Test 27

Verdict: ACCEPTED

Test 28

Verdict: ACCEPTED

Test 29

Verdict: ACCEPTED

Test 30

Verdict: ACCEPTED

Test 31

Verdict: ACCEPTED

Test 32

Verdict: ACCEPTED

Test 33

Verdict: ACCEPTED

Test 34

Verdict: ACCEPTED

Test 35

Verdict: ACCEPTED

Test 36

Verdict: ACCEPTED

Test 37

Verdict: ACCEPTED

Test 38

Verdict: ACCEPTED

Test 39

Verdict: ACCEPTED

Test 40

Verdict: ACCEPTED

Test 41

Verdict: ACCEPTED

Test 42

Verdict: ACCEPTED

Test 43

Verdict: ACCEPTED

Test 44

Verdict: ACCEPTED

Test 45

Verdict: ACCEPTED

Test 46

Verdict: ACCEPTED

Test 47

Verdict: ACCEPTED

Test 48

Verdict: ACCEPTED

Test 49

Verdict: ACCEPTED

Test 50

Verdict: ACCEPTED

Test 51

Verdict: ACCEPTED

Test 52

Verdict: ACCEPTED

Test 53

Verdict: ACCEPTED

Test 54

Verdict: ACCEPTED

Test 55

Verdict: ACCEPTED

Test 56

Verdict: TIME LIMIT EXCEEDED

Test 57

Verdict: TIME LIMIT EXCEEDED

Test 58

Verdict: TIME LIMIT EXCEEDED

Test 59

Verdict: TIME LIMIT EXCEEDED

Test 60

Verdict: TIME LIMIT EXCEEDED

Test 61

Verdict: TIME LIMIT EXCEEDED

Test 62

Verdict: TIME LIMIT EXCEEDED

Test 63

Verdict: TIME LIMIT EXCEEDED

Test 64

Verdict: TIME LIMIT EXCEEDED

Test 65

Verdict: TIME LIMIT EXCEEDED