programming/sites/leetcode/ReverseInteger.cpp at master · rp-code9/programming · GitHub

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
// https://leetcode.com/explore/interview/card/top-interview-questions-easy/127/strings/880/

#include <iostream>
#include <climits>

int reverse(int x)
{
    int reverse = 0;

    while (x != 0) {
        int pop = x % 10;

        if (reverse > INT_MAX / 10 || (reverse == INT_MAX / 10 && pop  > 7)) {
            return 0;
        }

        if (reverse < INT_MIN / 10 || (reverse == INT_MIN / 10 && pop < - 8)) {
            return 0;
        }

        reverse = reverse * 10 + pop;
        x = x / 10;
    }
    return reverse;
}


int main()
{
    std::cout << reverse(123) << std::endl;
    std::cout << reverse(-123) << std::endl;
    std::cout << reverse(120) << std::endl;
    std::cout << reverse(0) << std::endl;
    std::cout << reverse(100) << std::endl;
    std::cout << reverse(1534236469) << std::endl;

    return 0;
}