Optimising Arduino Code using PIN registers

int digits [10][7]{
  {1,1,1,1,1,1,0}, // digit 0
  {0,1,1,0,0,0,0}, // digit 1
  {1,1,0,1,1,0,1}, // digit 2
  {1,1,1,1,0,0,1}, // digit 3
  {0,1,1,0,0,1,1}, // digit 4
  {1,0,1,1,0,1,1}, // digit 5
  {1,0,1,1,1,1,1}, // digit 6
  {1,1,1,0,0,0,0}, // digit 7
  {1,1,1,1,1,1,1}, // digit 8
  {1,1,1,1,0,1,1}  // digit 9
};
void setup() {
  pinMode(0, OUTPUT);// Segment A
  pinMode(1, OUTPUT);// Segment B
  pinMode(2, OUTPUT);// Segment C
  pinMode(3, OUTPUT);// Segment D
  pinMode(4, OUTPUT);// Segment E
  pinMode(5, OUTPUT);// Segment F
  pinMode(6, OUTPUT);// Segment G
}
void display_digit(int d){
  if (digits[d][0]==1) digitalWrite(0, LOW); else digitalWrite(0, HIGH); //A
  if (digits[d][1]==1) digitalWrite(1, LOW); else digitalWrite(1, HIGH); //B
  if (digits[d][2]==1) digitalWrite(2, LOW); else digitalWrite(2, HIGH); //C
  if (digits[d][3]==1) digitalWrite(3, LOW); else digitalWrite(3, HIGH); //D
  if (digits[d][4]==1) digitalWrite(4, LOW); else digitalWrite(4, HIGH); //E
  if (digits[d][5]==1) digitalWrite(5, LOW); else digitalWrite(5, HIGH); //F
  if (digits[d][6]==1) digitalWrite(6, LOW); else digitalWrite(6, HIGH); //G
}
void loop() {
  for (int i=0;i<10;i++) {
    display_digit(i);
    delay(1000);
  }
}