求m~n之间的素数

int isPrime(int k)

{
int i;
for (i = 2; i < k; i++)
if (k % 2 == 0)return 0;
return 1;
}
int main()
{
int m, n, i;
printf(“input m and n:”);
scanf_s(“%d%d”, &m, & n);
printf(“prime number is”);
for (i = m; i <= n; i++)
if (isPrime(i) == 1)
printf(“%d”, i);

return 0;

}

个数计算：

int isPrime(int k)

{
int i;
for (i = 2; i < k; i++)
if (k % i == 0)return 0;
return 1;
}
int main()
{
int m, n, i,count;
count = 0;
printf(“input m and n:”);
scanf_s(“%d%d”, &m, & n);
printf(“prime number is”);
for (i = m; i <= n; i++)
if (isPrime(i) == 1)
count++;
printf(“%d”, count);

return 0;

}