题目来自：网络
Description
对于任意给定的两个整型数N和M，你需要做的事情是求出[N,M]之间的所有素数之和。我们确保0 <= N < M <= 100。
所谓素数即：只能被1及其自身整除的数。注：1不是素数。
Input
输入的数据仅包含两个整型数N和M，N和M之间用空格间隔
Output
输出只包含一个数，即[N, M]之间的素数之和
Sample Input
1 10
Sample Output
17
//-----------------------------------------------------------------------
//这个还是比较简单的
#include <iostream>
#include <cmath>
using namespace std;
void sum_sushu(int a,int b);
bool Is_sushu(int n);
int main()
{
int a,b;
cin >> a >> b;
sum_sushu(a,b);
return 0;
}
bool Is_sushu(int n)
{
if (n < 2)
{
return false;
}
int i,j;
for (i = 2,j = int(sqrt(n));i<=j;i++)
{
// cout << j<< endl; // Using cout to check how 'j' change
if ((n % i) == 0)
{
return false;
}
//cout << n % i << endl; // Using cout to check how ' n%i ' change
}
return true;
}
void sum_sushu(int a,int b)
{
int sum = 0;
for (int i = a;i <= b;i++)
{
if (Is_sushu(i))
{
sum += i;
//cout << i << " "; //Using cout to check how ' i ' change
}
}
cout << sum << endl;
}
//I like to cout some variables to check if they are right, and how they change
//Could you please send your codes to my e-mail ediszhao@sina.com If you have a better way to deal with it