Program #3 (U1): Simple Interest (SI) & Compound Interest (CI)
Task: Read principal (P), annual rate in percent (R), and time in years (T). Compute SI = (P×R×T)/100 and CI for annual compounding using A = P × (1 + R/100)T, then CI = A − P. Print both to two decimal places.
/* Program: Simple Interest & Compound Interest (U1) What it does: - Inputs principal P, annual rate R (in %), and time T (in years). - Computes: SI = (P * R * T) / 100. - Computes: Amount A = P * (1 + R/100)^T, then CI = A - P (annual compounding). Note: To compile on some systems you may need the math library: e.g., gcc file.c -o a.out -lm*/
#include <stdio.h>
#include <math.h> /* for pow() */
int main(void) {
double P, R, T; /* principal, rate(%), time(years) */
double SI, A, CI; /* simple interest, amount, compound interest */
printf("Enter Principal (P), Rate in %% per annum (R), and Time in years (T): ");
if (scanf("%lf %lf %lf", &P, &R, &T) != 3) {
printf("Invalid input. Please enter three numbers like: 10000 7.5 3\n");
return 0;
} /* Basic validation: principal and time non-negative; rate can be zero. */
if (P < 0 || T < 0) {
printf("Principal and Time must be non-negative.\n");
return 0;
} SI = (P * R * T) / 100.0;
A = P * pow(1.0 + R / 100.0, T);
CI = A - P; printf("Simple Interest (SI) = %.2f\n", SI);
printf("Compound Interest (CI, annual) = %.2f\n", CI);
printf("Total Amount (A) = %.2f\n", A);
/* Example:
Input: P=10000, R=7.5, T=3 SI = 2250.00 A = 12421.88, CI = 2421.88*/
return 0;
}