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C++ Programming/Code/Standard C Library/Functions/isdigit
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isdigit
#include <cctype>
int isdigit( int ch );
The function isdigit() returns non-zero if its argument is a digit between 0 and 9. Otherwise, zero is returned.
char c;
scanf( "%c", &c );
if( isdigit(c) )
printf( "You entered the digit %c\n", c );
Related topics isalnum - isalpha - iscntrl - isgraph - isprint - ispunct - isspace - isxdigit