C PROGRAMMING PROGRAM • STRINGS

Remove Spaces from a String

Learn how to remove spaces from a string using a clear C program.

BeginnerStringsIn-place filteringisspace()

PROBLEM UNDERSTANDING

Input and expected output

Sample input

Code Bhavya makes C clear

Sample output

Without spaces: CodeBhavyamakesCclear

COMPLETE C PROGRAM

Complete C implementation

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

int main(void)
{
    char text[300];
    int write = 0;

    fgets(text, sizeof text, stdin);
    for (int read = 0; text[read] != '\0'; read++) {
        if (!isspace((unsigned char) text[read])) text[write++] = text[read];
    }
    text[write] = '\0';
    printf("Without spaces: %s\n", text);
    return 0;
}

CURRENT STEP

Select Start to walk through the important lines.

SELECTED LINE

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EXPECTED OUTPUT FOR THE SAMPLE

Without spaces: CodeBhavyamakesCclear

0%Step 0 of 0

PROGRAM EXPLANATION

Algorithm and explanation

Read the required input values.
Copy only non-whitespace characters forward inside the same array.
Display the computed result.

Copy only non-whitespace characters forward inside the same array.

EFFICIENCY

Time and space complexity

Time complexity

O(n)

Auxiliary space

O(1)

DEBUGGING CHECKLIST

Common mistakes

Check this

Use the correct format specifier for every variable.

Check this

Initialize variables before using their values.

Check this

Check braces, semicolons and input order carefully.

Try it yourself

Practice: Run the program with the sample input, predict its output, and then test one boundary case of your own.