How to convert First Character in String to Uppercase in C - Step by Step Examples

How to convert First Character in String to Uppercase in C ?

Answer

To convert the first character of a string to uppercase in C, you can use the toupper function from the ctype.h library.

✐ Examples

1 Convert First Character to Uppercase

In this example,

We include the necessary headers stdio.h for standard input/output functions and ctype.h for character handling functions.
We create a character array named str with a string value.
We check if the first character of the string is a lowercase letter using the islower function.
If the first character is lowercase, we convert it to uppercase using the toupper function.
Finally, we print the modified string to standard output.

C Program

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

int main() {
    char str[] = "hello world";
    if (islower(str[0])) {
        str[0] = toupper(str[0]);
    }
    printf("%s\n", str);
    return 0;
}

Output

Hello world

2 Convert First Character of Each Word to Uppercase

In this example,

We include the necessary headers stdio.h for standard input/output functions and ctype.h for character handling functions.
We create a character array named str with a string value that contains multiple words.
We initialize a variable new_word to track the beginning of a new word.
The outer loop iterates over each character in the string.
The inner loop checks if the current character is the beginning of a new word (i.e., the first character or preceded by a space).
If the character is a lowercase letter and it's the start of a new word, we convert it to uppercase using the toupper function.
We update the new_word flag after encountering a space.
Finally, we print the modified string to standard output.

C Program

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

int main() {
    char str[] = "hello world, how are you?";
    int new_word = 1;

    for (int i = 0; str[i] != '\0'; i++) {
        if (new_word && islower(str[i])) {
            str[i] = toupper(str[i]);
        }
        new_word = (str[i] == ' ');
    }

    printf("%s\n", str);
    return 0;
}

Output

Hello World, How Are You?

Summary

In this tutorial, we learned How to convert First Character in String to Uppercase in C language with well detailed examples.

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How to convert First Character in String to Uppercase in C - Step by Step Examples

How to convert First Character in String to Uppercase in C ?

Answer

✐ Examples

1 Convert First Character to Uppercase

C Program

Output

2 Convert First Character of Each Word to Uppercase

C Program

Output

Summary

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