Implement the function f(x) = x3 + 2 * x2 – 3.
Input. Each line contains one real number x.
Output. For each value of x, print
the value of the function f(x) on
a separate line with four decimal places.
|
Sample input |
Sample output |
|
2.234 1 56 23.2 |
18.1309 0.0000 181885.0000 13560.6480 |
functions
The problem can be solved in two ways:
·
using a
loop: read x and print the value of f(x) on the fly;
·
implement f(x) as a function;
Read the input data until the end of the
file.
Algorithm
implementation
Read the input data until the end of the
file.
while(scanf("%lf",&x)
== 1)
{
For each test case compute and print the answer.
y = x * x * x + 2 * x
* x - 3;
printf("%.4lf\n",y);
}
Algorithm
implementation – function
Define the f function.
double f(double
x)
{
return x * x * x + 2 * x * x - 3;
}
Read the input data until the end of the
file. Compute and print the answer.
while(scanf("%lf",&x)
== 1)
printf("%.4lf\n",f(x));
Java implementation
import
java.util.*;
public class Main
{
static double
f(double x)
{
return x * x * x + 2 * x * x - 3;
}
public static void main(String[] args)
{
Scanner con = new Scanner(System.in);
while(con.hasNext())
{
double x = con.nextDouble();
System.out.println(f(x));
}
con.close();
}
}
Python implementation – function
import sys
Define the f
function.
def f(x):
return x
** 3 + 2 * x * x – 3
Read the input data until the end of the
file. Compute and print the answer.
for x in sys.stdin:
x = float(x)
print(f(x))
Python implementation
import sys
Read the input data until the end of the
file.
for x in sys.stdin:
For each test case compute and print the answer.
x
= float(x)
y
= x ** 3 + 2 * x * x – 3
print(y)