[大学计算] 小测1 答案

小写英文字符变大写字符

#include <iostream>
using namespace std;
int main()
{
    char c_lower;
    cin>>c_lower;
///////////begin////////
    char c_upper;
	if (c_lower <= 'z' && c_lower >= 'a')
    {
        c_upper = c_lower + 'A' - 'a';
    }
    else
    {
        c_upper = c_lower;
    }
	
	
	
	
	
	
///////////end//////////
	cout<<c_upper;
	return 0;
} 

阶乘求和

#include <iostream>
using namespace std;
int main()
{
	
	int m,n;
	cin>>m>>n;
    long int sum;
	//////////begin//////////
	if (m >= n)
	{
		cout << "输入错误";
		return 0;
	}
	int tmp = 1;
	sum = 0;
	for (int i = 1; i <= m; i ++)
	{
		tmp *= i;
	}
	for (int i = m + 1; i <= n + 1; i ++)
	{
		sum += tmp;
		tmp *= i;
	}

	
	/////////end///////////
    cout<<sum;
	
	return 0;
} 

两个数的最大公约数

#include <iostream>
using namespace std;

int main()
{
	int n1, n2;
	
	
	cin >> n1 >> n2;
	//////////begin///////////
	if (n1 < n2)
	{
		int a = n1;
		n1 = n2;
		n2 = a;
	}
	while (n1 % n2 != 0)
	{
		n1 = n1 % n2;
		int c = n1;
		n1 = n2;
		n2 = c;
	}
	int c = n1;
	n1 = n2;
	n2 = c;
	
	
	//////////end///////////
	cout  << n1;
	return 0;
}

找“完数”的个数

#include <iostream>
using namespace std;
//////////begin//////////

int getNumber(int);
	
/////////end///////////

int main()
{
	

	int n;
	cin >> n;

    cout<<getNumber(n);
	
	return 0;
}
//////////begin//////////

int getNumber(int n)
{
	int cnt = 0;
	for (int i = 2; i <= n; i ++)
	{
		int tot = 0;
		for (int j = 1; j <= i / 2; j ++)
		{
			if (i % j == 0)
			{
				tot += j;
			}
		}
		if (tot == i)
		{
			cnt ++;
		}
	}
	return cnt;
}
	
/////////end///////////