Question

Exercise 5.1

Please provide code for both parts A and B.

PART A

Modify the P5_0.cpp program (located below) and use the predefined function pow to compute the a^b power. Here is the definition of the pow function:

double pow (double base, double exponent);

i.e. pow takes two parameters of type double, a and b and its value returned is of type double. You need to use pow in a statement like this:

p = pow(a,b)

Please note that in order to use the pow predefined function, you need to include the cmath directive, i.e. #include.

Call your new program ex51.cpp.

Imagine, you wanted to compute hundreds of these calculations in a program. Can you use a while loop in the program to do so?

PART B

Improve the program of exercise 5.1 by using a while loop that asks the user to input a and b (of any type), computes the pow(a, b)[i.e computes p = pow(a,b)] and displays the result. Call your new improved program ex52.cpp.

CODE: P5_0.cpp program

// P5_0.cpp This C++ program computes the value of a^b for three cases.
#include
using namespace std;

int main(void)
{
      int i = 0;
      int a = 2, b = 4, p = 1;

      while(i < b) // computing 2^4
      {
             p = p * a;
             i++;
       }
       cout << a << " to the power of " << b << " is = " << p << endl;

      i = 0;
      p = 1;
      a = 3, b = 3;

      while(i < b) // computing 3^3
      {
             p = p * a;
             i++;
       }
       cout << a << " to the power of " << b << " is = " << p << endl;

      i = 0;
      p = 1;
      a = 5, b = 4;

      while(i < b) // computing 5^4
      {
             p = p * a;
             i++;
       }
       cout << a << " to the power of " << b << " is = " << p << endl;

       return 0;
}

Answer 1

Part A : exc51.cpp

Program :

#include<bits/stdc++.h>
using namespace std;

int main(void)
{  
   int i = 0;
   double a = 2, b = 4,p;
   p = pow(a,b);
cout << a << " to the power of " << b << " is = " << p << endl;
a = 3, b = 3;
p = pow(a,b);
cout << a << " to the power of " << b << " is = " << p << endl;  
a = 5, b = 4;
   p = pow(a,b);
cout << a << " to the power of " << b << " is = " << p << endl;
   return 0;
}

Output :

Imagine, you wanted to compute hundreds of these calculations in a program. Can you use a while loop in the program to do so?

Answer : Yes we can define while loop to compute hundreds of calculations in a program.please go through exc52.cpp program for clear explanation.  

Part B : exc52.cpp

Program :

#include<bits/stdc++.h>
using namespace std;

int main(void)
{  
   int i = 0,n;
   double a,b,p;
   cout << "Enter no.of times to compute values : ";
   cin >> n;
   while(i<n){
       cout << "Enter 'a' value : ";
       cin >> a;
       cout << "Enter 'b' value : ";
       cin >> b;
       p = pow(a,b);
   cout <<"\n" << a << " to the power of " << b << " is = " << p << "\n" << endl;
   i++;
   }
   return 0;
}

Output :