Number to Word and Even/Odd Classifier in C

Summary: This C program reads two integers as input and iterates through all integers between them (inclusive). It prints the English word for numbers 1 through 9, and for numbers greater than 9, it prints whether they are even or odd.

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

int main() {
    int a, b;
    scanf("%d\n%d", &a, &b);

    // Loop from a to b (inclusive)
    for (int n = a; n <= b; n++) {
        if (n >= 1 && n <= 9) {
            // Print the English representation for numbers 1 to 9
            switch(n) {
                case 1: printf("one\n"); break;
                case 2: printf("two\n"); break;
                case 3: printf("three\n"); break;
                case 4: printf("four\n"); break;
                case 5: printf("five\n"); break;
                case 6: printf("six\n"); break;
                case 7: printf("seven\n"); break;
                case 8: printf("eight\n"); break;
                case 9: printf("nine\n"); break;
            }
        } else {
            // For numbers greater than 9, print "even" if the number is even, otherwise print "odd"
            if (n % 2 == 0) {
                printf("even\n");
            } else {
                printf("odd\n");
            }
        }
    }

    return 0;
}

Explanation:

Input Reading:
The program uses scanf() to read two integer inputs, representing a range of values to evaluate.

Looping Through Range:
A for loop is used to iterate from a to b (inclusive), ensuring that each number in the range is processed.

Switch Statement:
A switch block handles numbers from 1 to 9, printing their English equivalents. This avoids repetitive if-else comparisons and offers clean readability.

Even/Odd Classification:
For numbers greater than 9, the program uses the modulo operator % to check if the number is divisible by 2. If so, it prints even, otherwise odd.

Conditional Structure:
The program demonstrates the use of combined logic with relational and logical operators like >=, <=, and &&.

Use of Header Files:
While only stdio.h is required for this specific program, other headers are harmless here but unnecessary for functionality.