C Program for Print individual digits as words without using if or switch.

In C programming, converting individual digits of a number to their corresponding words is commonly done using if-else or switch statements. However, we can achieve this more elegantly using an array of string pointers to map each digit (0-9) to its word representation.

Syntax

char *digitWords[] = {"ZERO", "ONE", "TWO", ..., "NINE"};
// Access digit word using: digitWords[digit]

Algorithm

START
Step 1 ? Declare int variables num, i and array of pointers char *alpha with values {"ZERO", "ONE", "TWO", "THREE", "FOUR", "FIVE", "SIX", "SEVEN", "EIGHT", "NINE"}
Step 2 ? Read or assign the number to convert
Step 3 ? Extract each digit from the number (using modulo and division or string conversion)
Step 4 ? For each digit, print the corresponding word from the alpha array
Step 5 ? Continue until all digits are processed
STOP

Method 1: Using sprintf() for Digit Extraction

This approach converts the number to a string and then processes each character −

#include <stdio.h>

int main() {
    int num = 900;
    int i;
    char *alpha[] = {"ZERO", "ONE", "TWO", "THREE", "FOUR", "FIVE", "SIX", "SEVEN", "EIGHT", "NINE"};
    char str[20];
    
    printf("Number: %d<br>", num);
    sprintf(str, "%d", num);
    
    printf("In words: ");
    for(i = 0; str[i] != '\0'; i++) {
        printf("%s ", alpha[str[i] - '0']);
    }
    printf("<br>");
    
    return 0;
}

Number: 900
In words: NINE ZERO ZERO 

Method 2: Using Mathematical Approach

This method extracts digits using modulo and division operations −

#include <stdio.h>

void printDigitsAsWords(int num) {
    char *words[] = {"ZERO", "ONE", "TWO", "THREE", "FOUR", "FIVE", "SIX", "SEVEN", "EIGHT", "NINE"};
    int digits[10], count = 0, i;
    
    if (num == 0) {
        printf("%s ", words[0]);
        return;
    }
    
    while (num > 0) {
        digits[count++] = num % 10;
        num /= 10;
    }
    
    for (i = count - 1; i >= 0; i--) {
        printf("%s ", words[digits[i]]);
    }
}

int main() {
    int number = 12045;
    
    printf("Number: %d<br>", number);
    printf("In words: ");
    printDigitsAsWords(number);
    printf("<br>");
    
    return 0;
}

Number: 12045
In words: ONE TWO ZERO FOUR FIVE 

Key Points

• The array index corresponds directly to the digit value (0-9).
• Method 1 is simpler but requires string conversion.
• Method 2 uses pure mathematical operations for digit extraction.
• Both methods avoid conditional statements like if-else or switch.

Conclusion

Using an array of string pointers provides an elegant solution to convert digits to words without conditional statements. The approach leverages array indexing to map digits directly to their word representations, making the code clean and efficient.