What is wrong with this code? it is for my University practical assignment..

Question

After a long time coding in C almost Forgot everything I find it very difficult.. help me correct the code
#include <stdio.h>
#include<string.h>
#include<ctype.h>

int main() {
char str[1000],digit String[1000] = {0};
printf ("\nEnter the string:");
gets(str);
char*ptr = strtok(str," ");
while (ptr)
{
int len = strlen(ptr);
bool integer = true ;
for (int i=0; i<len;i++)
{
if(isdigit (ptr[i]! = true))
{
integer = false;
break ;
}
}
if(integer ==true)
{
strcat(digit String,ptr);
strcat(digit String," ");
}
ptr = strtok (NULL," ") ;
}

printf ("\n\n Integer numbers within the string are:");
puts(digitString) ;
return 0;
}

Answer 1

Martin Taylor i see

Answer 2

C language doesn't have string & bool by default

Answer 3

Okay