Given three integers A, B and N, repeat the following process N times:
- Add a digit to A such that after adding it, A is divisible by B.
- Print the smallest value of A possible after N iterations of above above operation.
- Print -1 if the operation fails.
Note : We need to check divisibility after every digit addition.
Examples:
Input: A = 10, B = 11, N = 1
Output: -1
No matter what digit you add, 10X will never be divisible by 11.Input: A = 5, B = 3, N = 3
Output: 5100
Approach: Bruteforce for the first digit to be added from 0 to 9, if none of the digits make A divisible by B then the answer is -1. Otherwise add the first digit that satisfies the condition and then add 0 after that (n-1) times because if A is divisible by B then A*10, A*100, … will also be divisible by B.
Below is the implementation of the above approach:
C++
// C++ implementation of the approach#include <bits/stdc++.h>using namespace std; int addNDigits(int a, int b, int n){ int num = a; // Try all digits from (0 to 9) for (int i = 0; i <= 9; i++) { int tmp = a * 10 + i; if (tmp % b == 0) { a = tmp; break; } } // Fails in the first move itself if (num == a) return -1; // Add (n-1) 0's for (int j = 0; j < n - 1; j++) a *= 10; return a;} // Driver Program to test above functionint main(){ int a = 5, b = 3, n = 3; cout << addNDigits(a, b, n); return 0;} |
Java
//Java implementation of the approach import java.io.*; class GFG { static int addNDigits(int a, int b, int n){ int num = a; // Try all digits from (0 to 9) for (int i = 0; i <= 9; i++) { int tmp = a * 10 + i; if (tmp % b == 0) { a = tmp; break; } } // Fails in the first move itself if (num == a) return -1; // Add (n-1) 0's for (int j = 0; j < n - 1; j++) a *= 10; return a;} // Driver Program to test above function public static void main (String[] args) { int a = 5, b = 3, n = 3; System.out.print( addNDigits(a, b, n)); }}// This code is contributed by anuj_67.. |
Python3
# Python3 implementation of the approachdef addNDigits(a, b, n) : num = a # Try all digits from (0 to 9) for i in range(10) : tmp = a * 10 + i if (tmp % b == 0) : a = tmp break # Fails in the first move itself if (num == a) : return -1 # Add (n-1) 0's for j in range(n - 1) : a *= 10 return a # Driver Codeif __name__ == "__main__" : a = 5 b = 3 n = 3 print(addNDigits(a, b, n)) # This code is contributed by Ryuga |
C#
// C# implementation of the approachusing System; class GFG { static int addNDigits(int a, int b, int n){ int num = a; // Try all digits from (0 to 9) for (int i = 0; i <= 9; i++) { int tmp = a * 10 + i; if (tmp % b == 0) { a = tmp; break; } } // Fails in the first move itself if (num == a) return -1; // Add (n-1) 0's for (int j = 0; j < n - 1; j++) a *= 10; return a;} // Driver Codepublic static void Main () { int a = 5, b = 3, n = 3; Console.WriteLine(addNDigits(a, b, n));}} // This code is contributed // by anuj_67.. |
PHP
<?php// PHP implementation of the approach function addNDigits($a, $b, $n){ $num = $a; // Try all digits from (0 to 9) for ($i = 0; $i <= 9; $i++) { $tmp = $a * 10 + $i; if ($tmp % $b == 0) { $a = $tmp; break; } } // Fails in the first move itself if ($num == $a) return -1; // Add (n-1) 0's for ($j = 0; $j < $n - 1; $j++) $a *= 10; return $a;} // Driver Code$a = 5; $b = 3; $n = 3;echo addNDigits($a, $b, $n); // This code is contributed// by Akanksha Rai |
5100
Attention reader! Don’t stop learning now. Get hold of all the important mathematical concepts for competitive programming with the Essential Maths for CP Course at a student-friendly price. To complete your preparation from learning a language to DS Algo and many more, please refer Complete Interview Preparation Course.
