code-sliding-window-approach.cpp

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 *
 * Code for the book "DAILY 43: Algorithmic Problems for Coding Interviews: Easy level, C++ edition"
 *
 * Licensed under the GNU General Public License, Version 3.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
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 * distributed under the License is distributed on an "AS IS" BASIS,
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#include <iostream>
#include <string>
#include <cmath>
using namespace std;

int divisorSubstrings(int num, int k) {
    int num_of_digits = num == 0 ? 1 : (int) log10(abs(num)) + 1;
    long window_power = pow(10, k);
    int counts = num_of_digits - k + 1;
    int current_window = num % window_power;
    int remain = num / window_power;
    int beautyCount = 0;
    while (counts) {
        --counts;
        if (current_window!= 0 && num % current_window == 0)
            ++beautyCount;
        current_window = (remain % 10) * (window_power/10) + current_window / 10;
        remain = remain / 10;
    }
    return beautyCount;
}

int main() {
    // Example test cases
    int num1 = 120;
    int k1 = 2;
    cout << "Number of divisor substrings: " << divisorSubstrings(num1, k1) << endl; // Expected output: 2

    int num2 = 430043;
    int k2 = 2;
    cout << "Number of divisor substrings: " << divisorSubstrings(num2, k2) << endl; // Expected output: 2

    // Additional test cases
    int num3 = 555;
    int k3 = 1;
    cout << "Number of divisor substrings: " << divisorSubstrings(num3, k3) << endl; // Expected output: 3

    int num4 = 111;
    int k4 = 3;
    cout << "Number of divisor substrings: " << divisorSubstrings(num4, k4) << endl; // Expected output: 1

    return 0;
}