Javascript Program to Check if it is possible to make array increasing or decreasing by rotating the array

<script>
// javascript implementation of the approach    
// Function that returns true if the array
    // can be made increasing or decreasing
    // after rotating it in any direction
    function isPossible(a , n) {
        // If size of the array is less than 3
        if (n <= 2)
            return true;

        var flag = 0;

        // Check if the array is already decreasing
        for (i = 0; i < n - 2; i++) {
            if (!(a[i] > a[i + 1] && a[i + 1] > a[i + 2])) {
                flag = 1;
                break;
            }
        }

        // If the array is already decreasing
        if (flag == 0)
            return true;

        flag = 0;

        // Check if the array is already increasing
        for (i = 0; i < n - 2; i++) {
            if (!(a[i] < a[i + 1] && a[i + 1] < a[i + 2])) {
                flag = 1;
                break;
            }
        }

        // If the array is already increasing
        if (flag == 0)
            return true;

        // Find the indices of the minimum
        // && the maximum value
        var val1 = Number.MAX_VALUE, mini = -1, val2 = Number.MIN_VALUE, maxi = 0;
        for (i = 0; i < n; i++) {
            if (a[i] < val1) {
                mini = i;
                val1 = a[i];
            }
            if (a[i] > val2) {
                maxi = i;
                val2 = a[i];
            }
        }

        flag = 1;

        // Check if we can make array increasing
        for (i = 0; i < maxi; i++) {
            if (a[i] > a[i + 1]) {
                flag = 0;
                break;
            }
        }

        // If the array is increasing upto max index
        // && minimum element is right to maximum
        if (flag == 1 && maxi + 1 == mini) {
            flag = 1;

            // Check if array increasing again or not
            for (i = mini; i < n - 1; i++) {
                if (a[i] > a[i + 1]) {
                    flag = 0;
                    break;
                }
            }
            if (flag == 1)
                return true;
        }

        flag = 1;

        // Check if we can make array decreasing
        for (i = 0; i < mini; i++) {
            if (a[i] < a[i + 1]) {
                flag = 0;
                break;
            }
        }

        // If the array is decreasing upto min index
        // && minimum element is left to maximum
        if (flag == 1 && maxi - 1 == mini) {
            flag = 1;

            // Check if array decreasing again or not
            for (i = maxi; i < n - 1; i++) {
                if (a[i] < a[i + 1]) {
                    flag = 0;
                    break;
                }
            }
            if (flag == 1)
                return true;
        }

        // If it is not possible to make the
        // array increasing or decreasing
        return false;
    }

    // Driver code
    
        var a = [ 4, 5, 6, 2, 3 ];
        var n = a.length;

        if (isPossible(a, n))
            document.write("Yes");
        else
            document.write("No");

// This code contributed by umadevi9616
</script>