C Programming: Convert a string to lowercase

C String: Exercise-22 with Solution

Write a program in C to convert a string to lowercase.

Sample Solution:

C Code:

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

int main()
{
	int ctr=0;
	char str_char;
	char str[100]; 
    
	printf("\n Convert a string to lowercase :\n");  
    printf("----------------------------------");      
    printf("\n Input a string in UPPERCASE : ");
    fgets(str, sizeof str, stdin);  
    printf(" Here is the above string in lowercase :\n ");    
	while (str[ctr])
	{
		str_char=str[ctr];
		putchar (tolower(str_char));
		ctr++;
	}
	return 0;
}

Sample Output:

 Convert a string to lowercase :
----------------------------------
 Input a string in UPPERCASE : THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG.
 Here is the above string in lowercase :
 the quick brown fox jumps over the lazy dog.

Flowchart :

C Programming Code Editor:

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