Calculating the power of a number is a common task in programming. This article will explore various C Program to Calculate the Power of a Number, including iterative, recursive, and using built-in library functions. Each method will be explained with examples and outputs.
Prerequisites
Before diving into the examples, you should be familiar with:
- Basic C syntax and structure.
- Loops and conditional statements.
- Functions in C.
Understanding Power Calculation
The power of a number can be defined as x^n, where x is the base and n is the exponent. For example, 2^3 = 8
Example 1: Using Iteration
1.1 Explanation
This method involves multiplying the base by itself the number of times specified by the exponent.
1.2 Program: Iterative Method
#include <stdio.h>
int power(int base, int exp) {
int result = 1;
for(int i = 0; i < exp; i++) {
result *= base;
}
return result;
}
int main() {
int base, exp;
printf("Enter base: ");
scanf("%d", &base);
printf("Enter exponent: ");
scanf("%d", &exp);
printf("%d^%d = %d\n", base, exp, power(base, exp));
return 0;
}
1.3 Output
Enter base: 2
Enter exponent: 3
2^3 = 8
Example 2: Using Recursion
2.1 Explanation
Recursion can be used to calculate power by breaking down the problem into smaller subproblems.
2.2 Program: Recursive Method
#include <stdio.h>
int power(int base, int exp) {
if(exp == 0)
return 1;
else
return base * power(base, exp - 1);
}
int main() {
int base, exp;
printf("Enter base: ");
scanf("%d", &base);
printf("Enter exponent: ");
scanf("%d", &exp);
printf("%d^%d = %d\n", base, exp, power(base, exp));
return 0;
}
2.3 Output
Enter base: 2
Enter exponent: 3
2^3 = 8
Example 3: Using Built-in Library Function
3.1 Explanation
The C standard library provides a function pow() in the math.h header file to calculate the power of a number.
3.2 Program: Using pow() Function
#include <stdio.h>
#include <math.h>
int main() {
int base, exp;
printf("Enter base: ");
scanf("%d", &base);
printf("Enter exponent: ");
scanf("%d", &exp);
printf("%d^%d = %.0f\n", base, exp, pow(base, exp));
return 0;
}
3.3 Output
Enter base: 2
Enter exponent: 3
2^3 = 8
Example 4: Optimized Recursive Method (Exponential Squaring)
4.1 Explanation
Exponential squaring is an optimized recursive method to calculate power with reduced time complexity.
4.2 Program: Exponential Squaring
#include <stdio.h>
int power(int base, int exp) {
if(exp == 0)
return 1;
if(exp % 2 == 0) {
int halfPower = power(base, exp / 2);
return halfPower * halfPower;
} else {
return base * power(base, exp - 1);
}
}
int main() {
int base, exp;
printf("Enter base: ");
scanf("%d", &base);
printf("Enter exponent: ");
scanf("%d", &exp);
printf("%d^%d = %d\n", base, exp, power(base, exp));
return 0;
}
4.3 Output
Enter base: 2
Enter exponent: 3
2^3 = 8
Example 5: Using a Loop for Floating Point Exponents
5.1 Explanation
To handle non-integer exponents, we can use a loop-based approach that multiplies the base by itself fractional times.
5.2 Program: Loop for Floating Point Exponents
#include <stdio.h>
#include <math.h>
double power(double base, double exp) {
double result = 1.0;
for(int i = 0; i < (int)exp; i++) {
result *= base;
}
double fractionalPart = exp - (int)exp;
if(fractionalPart > 0) {
result *= pow(base, fractionalPart);
}
return result;
}
int main() {
double base, exp;
printf("Enter base: ");
scanf("%lf", &base);
printf("Enter exponent: ");
scanf("%lf", &exp);
printf("%.2f^%.2f = %.2f\n", base, exp, power(base, exp));
return 0;
}
5.3 Output
Enter base: 2.5
Enter exponent: 3.2
2.50^3.20 = 18.98
Conclusion
This article explored various C Program to Calculate the Power of a Number, including iterative, recursive, and using the built-in pow() function. Each method has its advantages and can be chosen based on the specific requirements of the problem. By understanding these different approaches, you can efficiently compute the power of a number in various scenarios.