Count of sub-strings that are divisible by K

<script>

// Javascript implementation of above approach 

// Function to return the count of sub-strings 
// of str that are divisible by k 
function countSubStr(str, len, k) 
{ 
    let count = 0; 
  
    for(let i = 0; i < len; i++) 
    { 
        let n = 0; 
  
        // Take all sub-strings starting from i 
        for(let j = i; j < len; j++)
        { 
            n = n * 10 + (str[j].charCodeAt() - 
                             '0'.charCodeAt()); 
  
            // If current sub-string is
            // divisible by k 
            if (n % k == 0) 
                count++; 
        } 
    } 
  
    // Return the required count 
    return count; 
} 

// Driver code
let str = "33445"; 
let len = str.length; 
let k = 11; 

document.write(countSubStr(str, len, k));

// This code is contributed by mukesh07

</script>

// JavaScript implementation of the approach
function divisible(s, k) {
  // To count substrings
  let num_of_substrings = 0;

  // To store the remainders
  let rem = new Array(k).fill(0);
  rem[0] = 1;
  let curr = "";

  // Iterate from len(s) - 1 to 0
  for (let i = s.length - 1; i >= 0; i--) {
    // to Calculate suffix string
    curr = s[i] + curr;

    // convert to number
    let num = parseInt(curr);
    num_of_substrings += rem[num % k];

    // Keep track of visited remainders
    rem[num % k] += 1;
  }

  // Return number of substrings
  return num_of_substrings;
}

// Driver Code
let s = "111111";
let k = 11;

// Function Call
console.log("Number of sub strings : ", divisible(s, k));


// This code is contributed by codebraxnzt