C/ctype.h/isdigit
int isdigit(int ch)
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//Header file: #include <ctype.h> //Declaration: int isdigit(int ch); //Return: returns nonzero if ch is a digit or zero is returned.
#include <ctype.h> #include <stdio.h> int main(void) { char ch; for(;;) { ch = getchar(); if(ch == "."){ break; } if(isdigit(ch)){ printf("%c is a digit\n", ch); } } return 0; }
/* 1 1 is a digit 2 2 is a digit 3 3 is a digit f .
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