Two Ways to Report a Bad Input

1#include <iostream>
2#include <stdexcept>
3 
4bool trySquareRoot(int value, int& result) noexcept {
5    if (value < 0) {
6        return false;
7    }
8    result = 0;
9    while ((result + 1) * (result + 1) <= value) {
10        result++;
11    }
12    return true;
13}
14 
15int squareRoot(int value) {
16    if (value < 0) {
17        throw std::domain_error("negative input");
18    }
19    int result = 0;
20    while ((result + 1) * (result + 1) <= value) {
21        result++;
22    }
23    return result;
24}
25 
26int main() {
27    int inputs[] = {16, -4, 10};
28    for (int value : inputs) {
29        int root = 0;
30        if (trySquareRoot(value, root)) {
31            std::cout << "code style: " << root << "\n";
32        } else {
33            std::cout << "code style: failed\n";
34        }
35        try {
36            int r = squareRoot(value);
37            std::cout << "exception style: " << r << "\n";
38        } catch (const std::domain_error& e) {
39            std::cout << "exception style: " << e.what() << "\n";
40        }
41    }
42    return 0;
43}