tolower() function in C
The tolower() function is defined in the ctype.h header file. If the character passed is a uppercase alphabet then the tolower() function converts a uppercase alphabet to an lowercase alphabet.
Syntax:
int tolower(int ch);
Parameter: This method takes a mandatory parameter ch which is the character to be converted to lowercase.
Return Value: This function returns the lowercase character corresponding to the ch.
Below programs illustrate the tolower() function in C:
Example 1:-
// C program to demonstrate// example of tolower() function. #include <ctype.h>#include <stdio.h> int main(){ // Character to be converted to lowercase char ch = 'G'; // convert ch to lowercase using toLower() printf("%c in lowercase is represented as = %c", ch, tolower(ch)); return 0;} |
Output:
G in lowercase is represented as = g
Example 2:-
// C program to demonstrate// example of tolower() function. #include <ctype.h>#include <stdio.h> int main(){ int j = 0; char str[] = "GEEKSFORGEEKS\n"; // Character to be converted to lowercase char ch = 'G'; // convert ch to lowercase using toLower() char ch; while (str[j]) { ch = str[j]; // convert ch to lowercase using toLower() putchar(tolower(ch)); j++; } return 0;} |
Output:
geeksforgeeks
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