AlphaNumeric seven segment arduino sketch with Bitshifting/bitmasking

sevenSeg.c

static unsigned char alphanum[37] = {0xEE, 0x3E, 0x9C, 0x7A, 0x9E, 0x8E, 0xBC, 0x6E, 0x0C, 0x78, 0xAE, 0x1C, 0xA8, 0xEC, 0xFC, 0xCE, 0xE6, 0xCC, 0xB6, 0x1E, 0x7C, 0x74, 0x54, 0x6E, 0x76, 0xD2, 0xFC, 0x60, 0xDA, 0xF2, 0x66, 0xB6, 0xBE, 0xE0, 0xFE, 0xF6, 0x00};
int pin_offset = 2; //the pin your 7seg starts at.

//used for cycling through characters
int iterator = 200; //just for demonstration purposes.
    
void printCharacter(char c_) {
    //if the character is a lowercase alpha, convert it to an uppercase.
    if(c_ >= 97 && c_ <= 122) {
      c_ -= 32;//lowercase letters appear 32 places higher in the ascii table
    }

    //convert ascii character indexes to our array index
    if(c_ >=65 && c_ <= 90) {//within the alpha range (A-Z)
      c_-=65; //in the ascii table, A is 65, and in our array, A is 0.
    }else if( c_ >= 48 && c_ <= 57){//within the number range (0-9)
      c_-=22; //in the ascii table, '0' is 48, but in our table, '0' is 26. We just use the difference of these two numbers.
    }else{ //something else
      c_ = 36; //this is an empty character. It lights up no segments.
    }
    
    for(int i = 0; i < 7; i++){//for each segment
      //take the byte representing each character
      //mask each bit, starting with the rightmost, and use these results as a bool.
      digitalWrite(i+pin_offset, 0x01 &( alphanum[c_] >> (7-i))); //we want the bit to be processed from the right to the left. so we use 7-i.
    }
}

void setup() {
  for (int i = pin_offset; i <= 7 + pin_offset; i++) {
    pinMode(i, OUTPUT);
  }
  Serial.begin(9600);
}

void loop() {
  iterator++;
  if (iterator > 48 + 9) { iterator = 48; }//num
  //if (iterator > 65 + 25) { iterator = 65; }//alpha
  
  printCharacter(iterator);
  delay(800);
}

//needs to be cleaned up a bit

//todo: reduce the digitalWrite forloop to 6, as the 8th bit is ALWAYS 0