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Download the file hwCalc.ypp.
Look at the file hwtok.cpp. Download it and compile and run like this: 
> g++ -o hwtok hwtok.cpp
> ./tok
3*(-4 + 12/3);
NUM[3] OPM[*] LP[(] OPA[-] NUM[4] OPA[+] NUM[12] OPM[/] NUM[3] RP[)] STOP[;]
Some changes to a language can be handled completely by the scanner. Your job is to modify hwtok.cpp so it can accept integers input in either decimal or binary. Specifically, a string of 0's and 1's followed immediately by a "b", no whitespace or anything, is an integer literal in binary. So, for example: 
> ./hwtok
10 + 3;
NUM[10] OPA[+] NUM[3] STOP[;]
101b + 3;
NUM[5] OPA[+] NUM[3] STOP[;]
  1. Draw a modified version of the finite automaton from the lecture notes that takes binary integer constants into account. Note: I am not requiring you to correctly handle strings like 1030b + ..., i.e. where the "b" is there, but the digits in front of it are not all 0's and 1's. Correct behavior would be to tokenize this as NUM[1030] Bad char b ... . I'm not asking you for that (though it would be cool!)
  2. Modify hwtok.cpp to implement this feature. You may use this function. 
    // Input:  val - a string consisting of the form (0|1)+b , e.g. 1011b 
// Output: the integer value equal to val (note: no error checking is done!)
int binary2int(const string &val)
{
  int x = 0;
  for(int i = 0; val[i] != 'b'; ++i)
    x = 2*x + (val[i]-'0');
  return x;
}
    Submit your code with: submit -c=SI413 -p=hw08 hwtok.cpp