#include <iostream>
#include <fstream>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>

using namespace std;
// check for keywords
int isKeyword(char buffer[]) {
  char keywords[32][10] = {
      "auto",     "break",  "case",    "char",   "const",    "continue",
      "default",  "do",     "double",  "else",   "enum",     "extern",
      "float",    "for",    "goto",    "if",     "int",      "long",
      "register", "return", "short",   "signed", "sizeof",   "static",
      "struct",   "switch", "typedef", "union",  "unsigned", "void",
      "volatile", "while"};
  int i, flag = 0;

  for (i = 0; i < 32; ++i) {
    if (strcmp(keywords[i], buffer) == 0) {
      flag = 1;
      break;
    }
  }

  return flag;
}
// Main function
int main() {
  char ch, buffer[15], operators[] = "+-*/%=";
  ifstream fin("program.txt");  // File containing the program
  int i, j = 0;

  if (!fin.is_open()) {
    cout << "error while opening the file\n";
    exit(0);
  }
  // iterate on the file containing the program to be analyzed
  while (!fin.eof()) {
    ch = fin.get();
    // get all the operators
    for (i = 0; i < 6; ++i) {
      if (ch == operators[i]) cout << ch << " is operator\n";
    }
    // get the numbers to be operated on
    if (isalnum(ch)) {
      buffer[j++] = ch;
    }
    // get the statements
    else if ((ch == ' ' || ch == '\n') && (j != 0)) {
      buffer[j] = '\0';
      j = 0;

      if (isKeyword(buffer) == 1)
        cout << buffer << " is keyword\n";
      else
        cout << buffer << " is indentifier\n";
    }
  }

  fin.close();

  return 0;
}