Block scheme on a game Simon says

Hi all,
I found alot of stuff on that game(schematics,sketch,prototipe) and is was helpfull so far.The only thing that I’m still searching is block scheme or block diagram on the sketch.I found a spider diagram but it does’t show all the nested operators which is essential for understanting the algorithm.
I’m asking for some giudelines on how the make block diagram(scheme) especially for nested operators,or if anyone made one to show me nesting.I’m using Robert Spann sketch

/* /*Simon Says game. Now with sound effects.

Originaly made by Robert Spann
Code trimmed and sound effects added by digimike

Buttons are to be set on there designated pins without pull down resistors
and connected to ground rather then +5.
*/
#include <Tone.h>
Tone speakerpin;
int starttune[] = {NOTE_C4, NOTE_F4, NOTE_C4, NOTE_F4, NOTE_C4, NOTE_F4, NOTE_C4, NOTE_F4, NOTE_G4, NOTE_F4, NOTE_E4, NOTE_F4, NOTE_G4};
int duration2[] = {100, 200, 100, 200, 100, 400, 100, 100, 100, 100, 200, 100, 500};
int note[] = {NOTE_C4, NOTE_C4, NOTE_G4, NOTE_C5, NOTE_G4, NOTE_C5};
int duration[] = {100, 100, 100, 300, 100, 300};
boolean button[] = {2, 3, 4, 5}; //The four button input pins
boolean ledpin[] = {8, 9, 10, 11};  // LED pins
int turn = 0;  // turn counter
int buttonstate = 0;  // button state checker
int randomArray[100]; //Intentionally long to store up to 100 inputs (doubtful anyone will get this far)
int inputArray[100]; 


void setup()
{
  Serial.begin(9600);
  speakerpin.begin(12); // speaker is on pin 13

  for(int x=0; x<4; x++)  // LED pins are outputs
  {
    pinMode(ledpin[x], OUTPUT);
  }
 
  for(int x=0; x<4; x++)
  {
    pinMode(button[x], INPUT);  // button pins are inputs
    digitalWrite(button[x], HIGH);  // enable internal pullup; buttons start in high position; logic reversed
  }

  randomSeed(analogRead(0)); //Added to generate "more randomness" with the randomArray for the output function
  for (int thisNote = 0; thisNote < 13; thisNote ++) {
     // play the next note:
     speakerpin.play(starttune[thisNote]);
     // hold the note:
     if (thisNote==0 || thisNote==2 || thisNote==4 || thisNote== 6)
     {
       digitalWrite(ledpin[0], HIGH);
     }
     if (thisNote==1 || thisNote==3 || thisNote==5 || thisNote== 7 || thisNote==9 || thisNote==11)
     {
       digitalWrite(ledpin[1], HIGH);
     }
     if (thisNote==8 || thisNote==12)
     {
       digitalWrite(ledpin[2], HIGH);
     } 
     if (thisNote==10)
     {  
       digitalWrite(ledpin[3], HIGH);
     }
     delay(duration2[thisNote]);
     // stop for the next note:
     speakerpin.stop();
     digitalWrite(ledpin[0], LOW);
     digitalWrite(ledpin[1], LOW);
     digitalWrite(ledpin[2], LOW);
     digitalWrite(ledpin[3], LOW);
     delay(25);
    }
  delay(1000);
}

void loop()
{  
  for (int y=0; y<=99; y++)
  {
    //function for generating the array to be matched by the player
    digitalWrite(ledpin[0], HIGH);
    digitalWrite(ledpin[1], HIGH);
    digitalWrite(ledpin[2], HIGH);
    digitalWrite(ledpin[3], HIGH);
 
    for (int thisNote = 0; thisNote < 6; thisNote ++) {
     // play the next note:
     speakerpin.play(note[thisNote]);
     // hold the note:
     delay(duration[thisNote]);
     // stop for the next note:
     speakerpin.stop();
     delay(25);
    }
   
    digitalWrite(ledpin[0], LOW);
    digitalWrite(ledpin[1], LOW);
    digitalWrite(ledpin[2], LOW);
    digitalWrite(ledpin[3], LOW);
    delay(1000);
 
    for (int y=turn; y <= turn; y++)
    { //Limited by the turn variable
      Serial.println(""); //Some serial output to follow along
      Serial.print("Turn: ");
      Serial.print(y);
      Serial.println("");
      randomArray[y] = random(1, 5); //Assigning a random number (1-4) to the randomArray[y], y being the turn count
      for (int x=0; x <= turn; x++)
      {
        Serial.print(randomArray[x]);
     
        for(int y=0; y<4; y++)
        {
     
          if (randomArray[x] == 1 && ledpin[y] == 8)
          {  //if statements to display the stored values in the array
            digitalWrite(ledpin[y], HIGH);
            speakerpin.play(NOTE_G3, 100);
            delay(400);
            digitalWrite(ledpin[y], LOW);
            delay(100);
          }

          if (randomArray[x] == 2 && ledpin[y] == 9)
          {
            digitalWrite(ledpin[y], HIGH);
            speakerpin.play(NOTE_A3, 100);
            delay(400);
            digitalWrite(ledpin[y], LOW);
            delay(100);
          }
 
          if (randomArray[x] == 3 && ledpin[y] == 10)
          {
            digitalWrite(ledpin[y], HIGH);
            speakerpin.play(NOTE_B3, 100);
            delay(400);
            digitalWrite(ledpin[y], LOW);
            delay(100);
          }

          if (randomArray[x] == 4 && ledpin[y] == 11)
          {
            digitalWrite(ledpin[y], HIGH);
            speakerpin.play(NOTE_C4, 100);
            delay(400);
            digitalWrite(ledpin[y], LOW);
            delay(100);
          }
        }
      }
    }
    input();
  }
}



void input() { //Function for allowing user input and checking input against the generated array

  for (int x=0; x <= turn;)
  { //Statement controlled by turn count

    for(int y=0; y<4; y++)
    {
     
      buttonstate = digitalRead(button[y]);
   
      if (buttonstate == LOW && button[y] == 2)
      { //Checking for button push
        digitalWrite(ledpin[0], HIGH);
        speakerpin.play(NOTE_G3, 100);
        delay(200);
        digitalWrite(ledpin[0], LOW);
        inputArray[x] = 1;
        delay(250);
        Serial.print(" ");
        Serial.print(1);
        if (inputArray[x] != randomArray[x]) { //Checks value input by user and checks it against
          fail();                              //the value in the same spot on the generated array
        }                                      //The fail function is called if it does not match
        x++;
      }
       if (buttonstate == LOW && button[y] == 3)
      {
        digitalWrite(ledpin[1], HIGH);
        speakerpin.play(NOTE_A3, 100);
        delay(200);
        digitalWrite(ledpin[1], LOW);
        inputArray[x] = 2;
        delay(250);
        Serial.print(" ");
        Serial.print(2);
        if (inputArray[x] != randomArray[x]) {
          fail();
        }
        x++;
      }

      if (buttonstate == LOW && button[y] == 4)
      {
        digitalWrite(ledpin[2], HIGH);
        speakerpin.play(NOTE_B3, 100);
        delay(200);
        digitalWrite(ledpin[2], LOW);
        inputArray[x] = 3;
        delay(250);
        Serial.print(" ");
        Serial.print(3);
        if (inputArray[x] != randomArray[x]) {
          fail();
        }
        x++;
      }

      if (buttonstate == LOW && button[y] == 5)
      {
        digitalWrite(ledpin[3], HIGH);
        speakerpin.play(NOTE_C4, 100);
        delay(200);
        digitalWrite(ledpin[3], LOW);
        inputArray[x] = 4;
        delay(250);
        Serial.print(" ");
        Serial.print(4);
        if (inputArray[x] != randomArray[x])
        {
          fail();
        }
        x++;
      }
    }
  }
  delay(500);
  turn++; //Increments the turn count, also the last action before starting the output function over again
}

void fail() { //Function used if the player fails to match the sequence

  for (int y=0; y<=2; y++)
  { //Flashes lights for failure
   
    digitalWrite(ledpin[0], HIGH);
    digitalWrite(ledpin[1], HIGH);
    digitalWrite(ledpin[2], HIGH);
    digitalWrite(ledpin[3], HIGH);
    speakerpin.play(NOTE_G3, 300);
    delay(200);
    digitalWrite(ledpin[0], LOW);
    digitalWrite(ledpin[1], LOW);
    digitalWrite(ledpin[2], LOW);
    digitalWrite(ledpin[3], LOW);
    speakerpin.play(NOTE_C3, 300);
    delay(200);
  }
  delay(500);
  turn = -1; //Resets turn value so the game starts over without need for a reset button
}
 
}