// 2.
#include <iostream>
#include <cmath>
#include <iomanip>
using namespace std;
const double PI = 3.14159;
int main()
{
double r, h; cin >> r >> h;
cout << setiosflags(ios::fixed) << setprecision(2); // 设置浮点数以固定位数显示 + 设置浮点数的精度为2位小数
cout << "圆周长: " << 2 * PI * r << endl;
cout << "圆面积: " << PI * pow(r, 2) << endl;
cout << "圆球表面积: " << 4 * PI * pow(r, 2) << endl;
cout << "圆球体积: " << 4.0 / 3 * PI * pow(r, 3) << endl;
cout << "圆柱体积:" << PI * pow(r, 2) * h << endl;
return 0;
}
#include <iostream>
using namespace std;
int main()
{
int f; cin >> f;
int c = 5.0 / 9 * (f - 32);
printf("%.2lf\n", c);
return 0;
}
#include <iostream>
using namespace std;
int main()
{
int a = 3, b = 4, c = 5;
cout << (a + b > c && b == c) << endl; // 0
cout << (a || b + c && b - c) << endl; // 1
cout << (!(a > b) && !c || 1) << endl; // 1
cout << (!(a + b) + c - 1 && + c / 2) << endl; // 1
return 0;
}
#include <iostream>
using namespace std;
int main()
{
int a,b,c; cin >> a >> b >> c;
cout << (a > b ? (a > c ? a : c) : (b > c ? b : c));
return 0;
}
#include <iostream>
using namespace std;
int a[5];
int main()
{
int n; cin >> n;
int cnt = 0;
int m = n;
for(int i = 0; i < 5; i++)
{
a[4 - i] = n % 10;
n /= 10;
}
for(int i = 0; i < 5; i++)
{
cout << a[i] << " ";
}
cout << endl;
while(m)
{
cout << m % 10 << " "; //
cnt++;
m /= 10;
}
cout << endl;
cout << cnt << endl;
return 0;
}
#include <iostream>
#include <algorithm>
using namespace std;
int a[4];
int main()
{
for(int i = 0; i < 4; i++)
{
cin >> a[i];
}
sort(a, a + 4);
for(int i = 0; i < 4; i++)
{
cout << a[i] << " ";
}
return 0;
}
#include <iostream>
#include <cmath>
using namespace std;
int main()
{
int a, n; cin >> a >> n; // a为数字,n为位数
int sum = 0;
int num = 0; // num用于保存上一次的结果
for(int i = 1; i <= n; i++)
{
num += pow(10, i - 1) * a;
sum += num;
}
cout << sum << endl;
return 0;
}
#include <iostream>
using namespace std;
int main()
{
int sum = 0;
int k = 1; // k计算遍历到谁的阶乘了
int num; cin >> num; // num表示一共需要计算到谁的阶乘为止
do
{
int c = 1;
for(int i = 1; i <= k; i++)
{
c *= i;
}
sum += c;
k++;
}while(k <= num);
cout << sum << endl;
return 0;
}
#include <iostream>
#include <cmath>
using namespace std;
int main()
{
for(int i = 100; i < 1000; i++)
{
int baiwei = i / 100;
int shiwei = i % 100 / 10;
int gewei = i % 10;
if(pow(baiwei,3) + pow(shiwei, 3) + pow(gewei, 3) == i)
{
cout << i << " ";
}
}
return 0;
}
#include <iostream>
using namespace std;
int main()
{
for(int i = 2; i <= 1000; i++)
{
int sum = 0;
for(int j = 1; j < i; j++)
{
if(i % j == 0)
{
sum += j;
}
}
if(sum == i)
{
cout << i << " ";
}
}
return 0;
}
#include <iostream>
using namespace std;
const int N = 20;
double a[N];
int main()
{
a[0] = 1.0, a[1] = 2.0;
for(int i = 2; i <= N; i++)
{
a[i] = a[i - 1] + a[i - 2];
}
double sum = 0;
for(int i = 1; i <= 20; i++)
{
sum += a[i + 1] / a[i];
}
cout << sum << endl;
return 0;
}