Assigning values to an array in "for" loop doesn't work

Hello,
I have a problem with this code:

double myarray[10][7] = {0};

void setup() {
  Serial.begin(9600);
  delay(1000);
  Serial.println("1");
  for (int s = 0; s < 10; s++) {
    Serial.println("lel");
    myarray[s][0] = 0;
    myarray[s][1] = 1;
    myarray[s][2] = 2;
    myarray[s][3] = 3;
    myarray[s][4] = 4;
    myarray[s][5] = 5;
    myarray[s][6] = 6;
    myarray[s][7] = 7;
    
  }
  Serial.println("2");
  for (int y = 0; y <= 10; y++) {
    Serial.print(myarray[y][0]);
    Serial.print("|__|");
    Serial.print(myarray[y][1]);
    Serial.print("|__|");
    Serial.print(myarray[y][2]);
    Serial.print("|__|");
    Serial.print(myarray[y][3]);
    Serial.print("|__|");
    Serial.print(myarray[y][4]);
    Serial.print("|__|");
    Serial.print(myarray[y][5]);
    Serial.print("|__|");
    Serial.print(myarray[y][6]);
    Serial.print("|__|");
    Serial.print(myarray[y][7]);
    Serial.print("\n");
  }

}

void loop() {
  // put your main code here, to run repeatedly:

}

It keeps printing one sign like this:

±
±
±
±
±
±
±
±
±
±
±
±
±
±
±

When I modify the code by deleting assigning operations from the first loop, it goes almost good, but there's another problem with some overflow. The modified code:

double myarray[10][7] = {0};

void setup() {
  Serial.begin(9600);
  delay(1000);
  Serial.println("1");
  for (int s = 0; s < 10; s++) {
    Serial.println("lel");
    
  }
  Serial.println("2");
  for (int y = 0; y <= 10; y++) {
    Serial.print(myarray[y][0]);
    Serial.print("|__|");
    Serial.print(myarray[y][1]);
    Serial.print("|__|");
    Serial.print(myarray[y][2]);
    Serial.print("|__|");
    Serial.print(myarray[y][3]);
    Serial.print("|__|");
    Serial.print(myarray[y][4]);
    Serial.print("|__|");
    Serial.print(myarray[y][5]);
    Serial.print("|__|");
    Serial.print(myarray[y][6]);
    Serial.print("|__|");
    Serial.print(myarray[y][7]);
    Serial.print("\n");
  }

}

The result:

1
lel
lel
lel
lel
lel
lel
lel
lel
lel
lel
2
0.00||0.00||0.00||0.00||0.00||0.00||0.00||0.00
0.00|
|0.00||0.00||0.00||0.00||0.00||0.00||0.00
0.00||0.00||0.00||0.00||0.00||0.00||0.00||0.00
0.00|
|0.00||0.00||0.00||0.00||0.00||0.00||0.00
0.00||0.00||0.00||0.00||0.00||0.00||0.00||0.00
0.00|
|0.00||0.00||0.00||0.00||0.00||0.00||0.00
0.00||0.00||0.00||0.00||0.00||0.00||0.00||0.00
0.00|
|0.00||0.00||0.00||0.00||0.00||0.00||0.00
0.00||0.00||0.00||0.00||0.00||0.00||0.00||0.00
0.00|
|0.00||0.00||0.00||0.00||0.00||0.00||ovf
ovf||ovf||ovf||0.00||ovf||0.00||ovf|__|-0.00

Could you help me with this?

your are going over the bounds of your declared array size:

double myarray[10][7] = {0};
. . .
. . .
myarray[s][7] = 7; // myarray[s][6] = 7; would be OK

It worked, thanks a lot!