Javascript Program to Find Maximum number of 0s placed consecutively at the start and end in any rotation of a Binary String

<script>

// Javascript program for the above approach

// Function to find the maximum sum of
// consecutive 0s present at the start
// and end of a string present in any
// of the rotations of the given string
function findMaximumZeros(str, n)
{
    // Check if all the characters
    // in the string are 0
    var c0 = 0;

    var i;
    // Iterate over characters
    // of the string
    for (i = 0; i < n; ++i) {
        if (str[i] == '0')
            c0++;
    }

    // If the frequency of '1' is 0
    if (c0 == n) {

        // Print n as the result
        document.write(n);
        return;
    }

    // Concatenate the string
    // with itself
    var s = str + str;

    // Stores the required result
    var mx = 0;
    var j;

    // Generate all rotations of the string
    for (i = 0; i < n; ++i) {

        // Store the number of consecutive 0s
        // at the start and end of the string
        var cs = 0;
        var ce = 0;
    
        // Count 0s present at the start
        for (j = i; j < i + n; ++j) {
            if (s[j] == '0')
                cs++;
            else
                break;
        }

        // Count 0s present at the end
        for (j = i + n - 1; j >= i; --j) {
            if (s[j] == '0')
                ce++;
            else
                break;
        }

        // Calculate the sum
        var val = cs + ce;

        // Update the overall
        // maximum sum
        mx = Math.max(val, mx);
    }

    // Print the result
    document.write(mx);
}

    // Driver Code
    // Given string
    var s = "1001";

    // Store the size of the string
    var n = s.length;

    findMaximumZeros(s, n);

</script>

<script>
//Javascript program for
//the above approach

// Function to find the maximum sum of
// consecutive 0s present at the start
// and end of any rotation of the string str
function findMaximumZeros(str, n)
{
    // Stores the count of 0s
    var c0 = 0;
    for (var i = 0; i < n; ++i) {
        if (str[i] == '0')
            c0++;
    }

    // If the frequency of '1' is 0
    if (c0 == n) {

        // Print n as the result
        document.write( n);
        return;
    }

    // Stores the required sum
    var mx = 0;

    // Find the maximum consecutive
    // length of 0s present in the string
    var cnt = 0;

    for (var i = 0; i < n; i++) {
        if (str[i] == '0')
            cnt++;
        else {
            mx = Math.max(mx, cnt);
            cnt = 0;
        }
    }

    // Update the overall maximum sum
    mx = Math.max(mx, cnt);

    // Find the number of 0s present at
    // the start and end of the string
    var start = 0, end = n - 1;
    cnt = 0;

    // Update the count of 0s at the start
    while (str[start] != '1' && start < n) {
        cnt++;
        start++;
    }

    // Update the count of 0s at the end
    while (str[end] != '1' && end >= 0) {
        cnt++;
        end--;
    }

    // Update the maximum sum
    mx = Math.max(mx, cnt);

    // Print the result
    document.write( mx);
}

var s = "1001";
// Store the size of the string
var n = s.length;

findMaximumZeros(s, n);

   
    
// This code is contributed by SoumikMondal
</script>