简单测试下Python、Go和C++的运行效率

        学习了一段时间的golang，想通过计算100000以内的素数个数测试下Golang的运行速率，并与C++和Python进行对比，具体实现如下：

Golang:

package main

import (
	"fmt"
	"time"
)

func main() {
	var count, state int
	start := time.Now()
	for outer := 2; outer < 100000; outer++ {
		state = 0
		for inner := 2; inner < outer; inner++ {
			if outer % inner == 0 {
				state = 1
				break
			}
		}
		if state == 0 {
			count++
		}
	}
	fmt.Println(count, " primes in 100000")
	elapse := time.Since(start)
	fmt.Println(elapse, "cost")
}

Python:

import time

count = 0

start = time.time()

for i in range(2, 100000):
    state = 0
    for j in range(2, i):
        if i % j == 0:
            state = 1
            break
    if not state:
        count += 1

elapse = time.time() - start

print(f'{count} primes in 100000')
print(f'{elapse}s cost')

C++:

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

int main() {
	clock_t start = clock();
	int count = 0, state = 0;
	for (int outer = 2; outer < 100000; outer++) {
		state = 0;
		for (int inner = 2; inner < outer; inner++) {
			if (outer % inner == 0) {
				state = 1;
				break;
			}
		}
		if (state == 0) {
			count++;
		}
	}
	cout << count << " primes in 100000" << endl;
	clock_t end = clock();
	cout << (double(end) - double(start)) / CLOCKS_PER_SEC << "s cost" << endl;
	return 0;
}

运行一下：

Golang：

Python：

C++：

        可以看到Go的运行效率更接近C++，均比Python高了一个量级