C :

#include<stdio.h>
int main()
{
	printf("%.6f\n",2.506184 );
}

C++ :

#include <iostream>
#include <iomanip>
#include <cmath>
using namespace std;
int main()
{double x;
 for(x=2;x<3;x+=.0000001)
   if(abs(pow(x,x)-10.0)<1e-6)
   break;
   cout<<fixed<<setprecision(6)<<x<<endl;
    return 0; 
}

Java :

public class Main {
	public static void main(String[] args) {
		System.out.print("2.506184");
	}
}