Keyword is a predefined or reserved word which is available in C++ library with a fixed meaning and used to perform an internal operation. C++ Language supports more than 64 keywords.
Every Keyword exists in lower case letters like auto, break, case, const, continue, int etc.
32 Keywords in C++ Language which is also available in the C language.
auto | double | int | struct |
break | else | long | switch |
case | enum | register | typedef |
char | extern | return | union |
const | float | short | unsigned |
continue | for | signed | void |
default | goto | sizeof | volatile |
do | if | static | while |
These are 30 reserved words that were not in C, but added to C++
asm | dynamic_cast | namespace | reinterpret_cast |
bool | explicit | new | static_cast |
catch | false | operator | template |
class | friend | private | this |
const_cast | inline | public | throw |
delete | mutable | protected | true |
try | typeid | typename | using |
using | using | wchar_t |
Input: str=”for” Output: for is a keyword
Explanation
Keywords are reserved words which cannot be used as variable names in program.
There are 32 keywords in the C programming language.
Compare the string with each keyword if the string is same then string is keyword
Example
#include <stdio.h> #include <string.h> int main() { char keyword[32][10]={ "auto","double","int","struct","break","else","long", "switch","case","enum","register","typedef","char", "extern","return","union","const","float","short", "unsigned","continue","for","signed","void","default", "goto","sizeof","voltile","do","if","static","while" } ; char str[]="which"; int flag=0,i; for(i = 0; i < 32; i++) { if(strcmp(str,keyword[i])==0) { flag=1; } } if(flag==1) printf("%s is a keyword",str); else printf("%s is not a keyword",str); }
Output
which is a keyword