isalnum() function in C programming language checks whether the given character is alphanumeric or not. isalnum() function defined in ctype.h header file.
Alphanumeric: A character that is either a letter or a number.
int isalnum(int x);
Input : 1 Output : Entered character is alphanumeric Input : A Output : Entered character is alphanumeric Input : & Output : Entered character is not alphanumeric
Entered character is alphanumeric
Application: isalnum() function is used to find out number of alphanumeric in a given sentence(or any input).
Input: abc123@ Output: Number of alphanumerics in the given input is : 6 Input: a@# Output: Number of alphanumerics in the given input is : 1 Input: ...akl567 Output: Number of alphanumerics in the given input is : 6
Number of alphanumerics in the given input is : 19
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