C++ :

#include <iostream>
#include <iomanip>
using namespace std;

int main() {
    double pi;
    cin >> pi;
    cout << "Default precision: " << pi << endl;
    cout << "Set precision to 2: " << setprecision(2) << pi << endl;
    cout << "Set precision to 4: " << setprecision(4) << pi << endl;
    return 0;
}