how to write a program that prints the largest value that occurs simultaneously in both arrays?

Question

I have to create two 10-elements arrays with random values from 1 to 20 and write a program that prints the largest value that occurs simultaneously in both arrays.

I created two tabs like below. The program should prints the largest value that occurs simultaneously in both arrays. Here it should be 11. I know just how to catch the max value from the array. I appreciate help.

<script>
var max = 0;
var tab = [1, 2, 5, 8, 9, 11, 15, 16, 17, 20];
var tab2 = [3, 4, 6, 7, 10, 11, 12, 13, 14, 18];
for (var i = 0; i < tab.length; i++) {
if (max <= tab[i]) {
max = tab[i];
}
}
console.log(max);
</script>

Answer 1

to find the largest value use nested loops to compare each element of both arrays as follow

var tab = [1, 2, 5, 8, 9, 11, 15, 16, 17, 20];
var tab2 = [3, 4, 6, 7, 10, 11, 12, 13, 14, 18];
var max = 0;
for (var i = 0; i < tab.length; i++) {
  for (var j = 0; j < tab2.length; j++) {
    if (tab[i] === tab2[j] && tab[i] > max) {
      max = tab[i];
    }
  }
}
console.log(max);