Mega Code Archive

Using functions isdigit, isalpha, isalnum, and isxdigit

#include <stdio.h> #include <ctype.h> int main() { printf( "%s\n%s%s\n%s%s\n\n", "According to isdigit: ", isdigit( '8' ) ? "8 is a " : "8 is not a ", "digit", isdigit( '#' ) ? "# is a " : "# is not a ", "digit" ); printf( "%s\n%s%s\n%s%s\n%s%s\n%s%s\n\n", "According to isalpha:", isalpha( 'A' ) ? "A is a " : "A is not a ", "letter", isalpha( 'b' ) ? "b is a " : "b is not a ", "letter", isalpha( '&' ) ? "& is a " : "& is not a ", "letter", isalpha( '4' ) ? "4 is a " : "4 is not a ", "letter" ); printf( "%s\n%s%s\n%s%s\n%s%s\n\n", "According to isalnum:", isalnum( 'A' ) ? "A is a " : "A is not a ", "digit or a letter", isalnum( '8' ) ? "8 is a " : "8 is not a ", "digit or a letter", isalnum( '#' ) ? "# is a " : "# is not a ", "digit or a letter" ); printf( "%s\n%s%s\n%s%s\n%s%s\n%s%s\n%s%s\n", "According to isxdigit:", isxdigit( 'F' ) ? "F is a " : "F is not a ", "hexadecimal digit", isxdigit( 'J' ) ? "J is a " : "J is not a ", "hexadecimal digit", isxdigit( '7' ) ? "7 is a " : "7 is not a ", "hexadecimal digit", isxdigit( '$' ) ? "$ is a " : "$ is not a ", "hexadecimal digit", isxdigit( 'f' ) ? "f is a " : "f is not a ", "hexadecimal digit" ); return 0; } According to isdigit: 8 is a digit # is not a digit According to isalpha: A is a letter b is a letter & is not a letter 4 is not a letter According to isalnum: A is a digit or a letter 8 is a digit or a letter # is not a digit or a letter According to isxdigit: F is a hexadecimal digit J is not a hexadecimal digit 7 is a hexadecimal digit $ is not a hexadecimal digit f is a hexadecimal digit