一个算法题搞不懂[推荐]

[sihonglaoren]

题目：

端午节到了，红星小学组织学生植树。第一个学生种一棵树，第二个学生种两棵树，第三个学生种三棵树，红星小学一共有小学生250名。问一共种了多少树？

要求：

要求编写程序打印输出。

请给出源代码。

[bdmh]

            int sum = 0;
            for (int i = 0; i < 250; i++)
            {
                sum += i + 1;
            }
            Console.WriteLine(sum);

[sihonglaoren]

谢谢！搞错了，是350名小学生。请问程序怎么写？

[hackerjoy]

#include<iostream>
using namespace std;
int main()
{
int count = 0;
for( int i = 0; i < 250 ; i++)
{
count += i+1;
}
cout<<count<<endl;
return 0;
}

[sihonglaoren]

[Quote=引用 3 楼 chikerstruggle 的回复:]
#include<iostream>
using namespace std;
int main()
{
int count = 0;
for( int i = 0; i < 250 ; i++)
{
count += i+1;
}
cout<<count<<endl;
return 0;
}
[/Quote]
不行啊

Error 1 Preprocessor directive expected c:\documents and settings\administrator\my documents\visual studio 2010\Projects\ConsoleApplication1\ConsoleApplication1\Program.cs 1 2 ConsoleApplication1
Error 2 Single-line comment or end-of-line expected c:\documents and settings\administrator\my documents\visual studio 2010\Projects\ConsoleApplication1\ConsoleApplication1\Program.cs 1 9 ConsoleApplication1
Error 3 Identifier expected; 'namespace' is a keyword c:\documents and settings\administrator\my documents\visual studio 2010\Projects\ConsoleApplication1\ConsoleApplication1\Program.cs 2 7 ConsoleApplication1
Error 4 { expected c:\documents and settings\administrator\my documents\visual studio 2010\Projects\ConsoleApplication1\ConsoleApplication1\Program.cs 2 20 ConsoleApplication1
Error 5 } expected c:\documents and settings\administrator\my documents\visual studio 2010\Projects\ConsoleApplication1\ConsoleApplication1\Program.cs 12 2 ConsoleApplication1

[sihonglaoren]

[Quote=引用 1 楼 bdmh 的回复:]
C# code


int sum = 0;
for (int i = 0; i < 250; i++)
{
sum += i + 1;
}
Console.WriteLine(sum);
[/Quote]
这个程序不对哦

Error 1 A namespace cannot directly contain members such as fields or methods c:\documents and settings\administrator\my documents\visual studio 2010\Projects\ConsoleApplication1\ConsoleApplication1\Program.cs 1 13 ConsoleApplication1

[threenewbee]

端午节植树？lz真逗

[wind_and_cloud]

private int Sun(int num)
{
int result = 0;
for (int i = 0; i <= num; i++)
{
result = result + i;
}
return result;
}

[youcx2010]

这个很难吗？不就求和 还扯得上算法？

[种草德鲁伊]

[推荐]

[yelang]

算法我就先不说了，我挺替第350个学生担心的，350棵树啊。

[种草德鲁伊]

[leonhd]

需要算法么？！
int f_sum(int n）
{
return (n * (n + 1)) / 2;
}

有多少个学生，返回f_sum(学生数)即可