POJ 3295 Tautologyシミュレーション

題意:文字列が本物かどうかを判断する.
Definitions of K, A, N, C, and E
     w  x
  Kwx
  Awx
   Nw
  Cwx
  Ewx
  1  1
  1
  1
   0
  1
  1
  1  0
  0
  1
   0
  0
  0
  0  1
  0
  1
   1
  1
  0
  0  0
  0
  0
   1
  1
  1
題解:p,q,r,s,tのブール値を列挙し,整数で表す.

#include <iostream>
using namespace std;

int Nth_Char;
char str[101];

bool step ( char str[101], int logicValue )
{
	Nth_Char++;
	switch ( str[Nth_Char] )
	{
	case 'p': return logicValue & 1;
	case 'q': return ( logicValue >> 1 ) & 1;
	case 'r': return ( logicValue >> 2 ) & 1;
	case 's': return ( logicValue >> 3 ) & 1;
	case 't': return ( logicValue >> 4 ) & 1;
	case 'N': return !step ( str, logicValue );
	case 'K': return step ( str, logicValue ) & step ( str, logicValue );   
	case 'A': return step ( str, logicValue ) | step ( str, logicValue );
	case 'C': return !step (str, logicValue ) | step ( str, logicValue );
	case 'E': return step ( str, logicValue ) == step ( str, logicValue );
	default:;
	}
}

bool judge ( char str[101] )
{
	for ( int i = 0; i < 32; i++ )  /*   p,q,r,s,t     */
	{
		Nth_Char = -1;
		if ( !step ( str, i ) )
			return false;
	}
	return true;
}

int main()
{
	while ( cin >> str && str[0] != '0' )
	{
		if ( judge ( str ) )
			cout << "tautology" << endl;
		else
			cout << "not" << endl;
	}
	return 0;PO
}