The program below takes two integers from the user (a base number and an exponent) and calculates the power.
For example: In the case of 23
- 2 is the base number
- 3 is the exponent
- And, the power is equal to
2*2*2
Power of a Number Using the while Loop
#include <stdio.h> int main() { int base, exp; long double result = 1.0; printf("Enter a base number: "); scanf("%d", &base); printf("Enter an exponent: "); scanf("%d", &exp); while (exp != 0) { result *= base; --exp; } printf("Answer = %.0Lf", result); return 0; } Output
Enter a base number: 3 Enter an exponent: 4 Answer = 81
We can also use the pow() function to calculate the power of a number.
Power Using pow() Function
#include <math.h> #include <stdio.h> int main() { double base, exp, result; printf("Enter a base number: "); scanf("%lf", &base); printf("Enter an exponent: "); scanf("%lf", &exp); // calculates the power result = pow(base, exp); printf("%.1lf^%.1lf = %.2lf", base, exp, result); return 0; } Output
Enter a base number: 2.3 Enter an exponent: 4.5 2.3^4.5 = 42.44
The programs above can only calculate the power of the base number if the exponent is positive. For negative exponents, use the following mathematical logic:
base(-exponent) = 1 / (baseexponent) For example, 2-3 = 1 / (23)