#include<iostream> // cin\cout\endl #include<cstdio> //scanf()\printf() #include<cstring> // strcpy()\strcat()\strcmp()\strlen()\memset() #include<cmath> //sqrt()\pow()\abs()\ceil()\floor()\max()\min() using namespace std; int main(){ double a; a=3.1415926; cout<<a<<endl; cout<<a*3*3<<endl; cout<<a*5*5<<endl; cout<<a*7*7<<endl; cout<<a*9*9<<endl; return 0; }