V>if((str[0]=='h'||str[0]=='H')
V>   &&(str[1]=='t'||str[1]=='T')
V>   &&(str[2]=='t'||str[2]=='T')
V>   &&(str[3]=='p'||str[3]=='P'))
V>

int state = 0;
bool result = false;
int pos = 0;
while (state!=5)
{
  char ch = str[pos++]
  switch(state)
  {
  case 0:
    if (ch =='h') 
    {
      state = 1;
      break
    }
    if (ch =='H') 
    {
      state = 1;
      break
    }
    state = 5;
    breack
  case 1:
    if (ch =='t') 
    {
      state = 2;
      break
    }
    if (ch =='T') 
    {
      state = 2;
      break
    }
    state = 5;
    breack
  case 2:
    if (ch =='t') 
    {
      state = 3;
      break
    }
    if (ch =='T') 
    {
      state = 3;
      break
    }
    state = 5;
    breack
  case 3:
    if (ch =='p') 
    {
      state = 5;
      result = true;
      break
    }
    if (ch =='P') 
    {
      state = 5;
      result = true;
      break
    }
    state = 5;
    break
  }
  if (result) ...
}