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C Program to covert character to lowercase using tolower() Function

In this program we will convert all the characters of an input string into string of lowercase characters. We will be using a system defined function tolower() defined under the ctype.h library.

tolower() takes a character as an input and converts it into an equivalent lowercase character

putchar() is used to print a single character at a time on the console.

Below is the program on tolower() function, try running the program and see how the program will print all the information along with the program.

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

int main()
{
    printf("\n\n\t\tStudytonight - Best place to learn\n\n\n");
    printf("putchar() is used to print a single character at a time on the console.\n\n\n");
    printf("tolower() takes a character as an input and converts it into an equivalent lower-case character.\n\n\n");
    printf("This can also be achieved by adding 32 to each uppercase character\n to get its equivalent lowercase format in ASCII. \n\n\n");
    printf("For example, ASCII value of a = %d and that of A = %d.\n\n\n ", 'a', 'A');
    printf("\n\nLet's first get the concept:\n ");
    printf("\n\nThe lowercase equivalent of letter 'A' is '%c' ",'A'+32);

    int aj = 0;
    char mj[] = " \n\n\n\n\"KEEP LEARNING, AS WHAT YOU KNOW WILL NEVER BE ENOUGH!\"\n\n";    // original uppercase string

    while(mj[aj])   // until string terminates
    {
        // converting one character at a time
        putchar(tolower(mj[aj]));
        aj++;
    }

    printf("\n\n\t\t\tCoding is Fun !\n\n\n");
    return 0;
}

Output:

tolower() function program