C Programming: Replace the spaces of a string with a specific character

Last update on August 06 2025 13:02:30 (UTC/GMT +8 hours)

25. Replace Spaces with Specific Character

Write a program in C to replace the spaces in a string with a specific character.

Sample Solution:

C Code:

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

int main() {
    int new_char;
    char t; // Variable to store the character to replace spaces
    int ctr = 0; // Counter variable
    char str[100]; // Array to store the input string

    printf("\n Replace the spaces of a string with a specific character :\n");
    printf("-------------------------------------------------------------\n");
    printf(" Input a string : ");
    fgets(str, sizeof str, stdin); // Read a string from the user including spaces
    printf(" Input replace character : ");
    scanf("%c", &t); // Read the character to replace spaces with

    printf(" After replacing the space with  %c the new string is :\n", t);
    while (str[ctr]) {
        new_char = str[ctr]; // Retrieve character from the string

        // Check if the character is a space and replace it with the specified character
        if (isspace(new_char)) {
            new_char = t;
        }

        putchar(new_char); // Print the character
        ctr++; // Move to the next character in the string
    }
    printf("\n\n");
    return 0; // Return 0 to indicate successful execution of the program
}

Output:

 Replace the spaces of a string with a specific character :
-------------------------------------------------------------
 Input a string : Be glad to see the back of
 Input replace character : *
 After replacing the space with  * the new string is :
 Be*glad*to*see*the*back*of*

Flowchart:

Flowchart: Replace the spaces of a string with a specific character

For more Practice: Solve these Related Problems:

Write a C program to replace every space in an input string with an asterisk (*) using a loop.
Write a C program to replace spaces in a string with a user-specified character, ensuring the original length is maintained.
Write a C program to convert multiple consecutive spaces in a string into a single specified delimiter.
Write a C program to change all whitespace characters in a string to hyphens (-) without using library functions.

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C Programming Code Editor:

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