luc098.c

Metadata

• Author — Amit Dutta
• Last updated — 08 Feb 2026
• License — MIT License (See the LICENSE file for details)

Problem Statement

Problem Statement

Write a calculator utility using command line arguments.\nUsage: calc <switch> <n> <m>\nwhere switch is arithmetic operator or comparison operator.

Source Code

View on GitHub Download Raw

Printing the code

To print this file, open it on GitHub and click Raw before printing, or use the Download Raw button above and print directly from that page.

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>

int main(int argc, char *argv[])
{
    float n, m, res;
    char operator;

    if (argc != 4)
    {
        printf("Usage: %s <switch> <n> <m>\n", argv[0]);
        printf("Example: %s + 10 20\n", argv[0]);
        printf("Note: For multiplication (*), use '*' or x to avoid shell expansion.\n");
        exit(1);
    }

    operator = argv[1][0]; // First character of the switch argument
    n = atof(argv[2]);
    m = atof(argv[3]);

    switch (operator)
    {
    // Arithmetic
    case '+':
        printf("%.2f\n", n + m);
        break;
    case '-':
        printf("%.2f\n", n - m);
        break;
    case 'x': 
    case '*':
        printf("%.2f\n", n * m);
        break;
    case '/':
        if (m == 0) printf("Error: Division by zero\n");
        else printf("%.2f\n", n / m);
        break;
    case '%':
        printf("%d\n", (int)n % (int)m);
        break;

    // Comparison
    case '<':
        printf("%s\n", (n < m) ? "True" : "False");
        break;
    case '>':
        printf("%s\n", (n > m) ? "True" : "False");
        break;
    
    // Handling symbols that might be multi-char (e.g. <=, >=, ==) is tricky 
    // with argv[1][0], but basic logic for typical single char switches:
    case '=':
        printf("%s\n", (n == m) ? "True" : "False");
        break;

    default:
        printf("Unknown operator: %c\n", operator);
        break;
    }

    return 0;
}