Find the largest value in array

When you write a Java method[^] you can specify a return type - a type of value that the method passes back to the caller when it is finished. The return type can be anything: integer, double, boolean, a class you wrote: any single type name that you can put in front of a variable name when you declare it.

And the system then knows that you will provide a value when the method is called. To provide that value, you use the return statement supplying the value to return.
For example, a JAva method to add two numbers could be:

static int Add(int x, int y){
   int result = x + y;
   return result;
}

This takes two parameters called x and y both of which are integers, adds them together, and returns the resulting value.

Your need for a return in your code means you probably need a method which accepts an array of integers, and returns an integer:

static int GetBiggest(int[] arr){
   int biggest;
   ...
   return biggest;
}

All you need to do is fill in the code in the middle.

Try

public class Max
{ 
  public static int findMax( int a[])
  {
    int max = a[0];
    for( int x : a)
      if ( max < x )
        max = x;
    return max;
  }

  public static void main(String args[] )
  {
    int A[] = {1, 8, 7, 56, 90 };

    int max = findMax(A);
    System.out.printf("Maximum value is %d\n", max);

  }
}