[Functions]D. Liang 5.16 Determining prime number
Description
An integer greater than 1 is a prime number if its only divisor is 1 or itself.
Write a function in the header file that determines whether an integer is a prime number.
For example, isPrime(11) return true, and isPrime(9) return false.
Hint
You should submit the implementation of the function but do not submit the main() function.
#ifndef SOURCE_H
#define SOURCE_H
int isPrime(int);
#endif
#include "source.h"
#include <stdio.h>
int main() {
int count = 0;
int i;
for (i = 2; count < 1000; i++)
{
// Display each number in five positions
if (isPrime(i))
{
//cout << setw(5) << i;
count++;
//if (count % 10 == 0) cout << endl;
}
}
printf("%d", --i);
return 0;
}
int isPrime(int n)//定义函数 判断一个数是否为素数
{
int i = 0;//定义参数 控制循环
for (i = 2; i < n; i++)
{
if (n % i == 0)//判断这个数与2至本身相模 是否有为零的数
//如果有则不是素数 没有则是
return 0;//有模为零的数 直接返回-1
}
return 1;//执行完循环还没有模为零的数 则是个素数 返回0
}