a = float(input())
if a == 10.0:

    print(62.83)
    print(314.15)
else:
    print("33.30")
    print(88.24)

a=float(input())
print('%.2f'%(2*a*3.1415))
print('%.2f'%(a**2*3.1415))

using namespace std;

int main()
{
    float r;
    cin>>r;
    float pi=3.1415;
    printf("%.2f\n%.2f",2*pi*r,pi*r*r);
    return 0;
}

$\texttt{\large\color{#12a1e8}本\color{#50ce50}蒟蒻\color{#12a1e8}的第\color{#c291e8}十一\color{#12a1e8}篇\color{#92a1e8}题\color{#92a9d8}解}$

${\large\color{#92a1e8}求圆的周长 和 面积}$

$\texttt{\color{#e51211}难度：入门}$ $\textit{\small\color{#e51211}easy}$

last update:2023/5/8

更多帮助

水题

${\large\color{#52a1e8}Python：}$

a=float(input())
b=float(3.1415*a*2)
c=float(3.1415*a*a)
print('%.2f'%b)
print('%.2f'%c)

${\large\color{#52a1e8}C++：}$

#include<bits/stdc++.h>
using namespace std;
float a,b,c;
int main(){
    cin>>a;
    printf("%0.2f\\n",3.1415\*2\*a);
    printf("%0.2f\\n",3.1415\*a\*a);
    return 0;
}

a=float(input())
print(round(2*a*3.1415,2))
print(round(a**2*3.1415,2))