sqrt.cpp

#include <iostream>
#include <chrono>
#include <cmath>

int mySqrt(int x) {
    return static_cast<int>(std::pow(x, 0.5));
}

int myFasterSqrt(int x) {
    if (x == 0 || x == 1) return x;
    
    int L = 1, R = x / 2;
    while (L <= R) {
        int M = L + (R - L) / 2;
        long long M_squared = static_cast<long long>(M) * M; // Избегаем переполнения
        
        if (M_squared == x) 
            return M;
        else if (M_squared < x) 
            L = M + 1;
        else 
            R = M - 1;
    }
    return R;
}

int main() {
    int x = 240000000;
    
    // Тест mySqrt
    auto start = std::chrono::high_resolution_clock::now();
    int result1 = mySqrt(x);
    auto end = std::chrono::high_resolution_clock::now();
    auto duration = std::chrono::duration_cast<std::chrono::nanoseconds>(end - start);
    std::cout << "mySqrt: " << result1 << " (Time: " << duration.count() << " ns)\n";

    // Тест myFasterSqrt
    start = std::chrono::high_resolution_clock::now();
    int result2 = myFasterSqrt(x);
    end = std::chrono::high_resolution_clock::now();
    duration = std::chrono::duration_cast<std::chrono::nanoseconds>(end - start);
    std::cout << "myFasterSqrt: " << result2 << " (Time: " << duration.count() << " ns)\n";

    // Тест std::sqrt
    start = std::chrono::high_resolution_clock::now();
    int result3 = static_cast<int>(std::sqrt(x));
    end = std::chrono::high_resolution_clock::now();
    duration = std::chrono::duration_cast<std::chrono::nanoseconds>(end - start);
    std::cout << "std::sqrt: " << result3 << " (Time: " << duration.count() << " ns)\n";
}