The correct, optimal and working solution for programming question lisa-workbook on hackerrank

/* * Author: Arpit Bhayani * https://arpitbhayani.me */ #include <cmath> #include <cstdio> #include <cstdlib> #include <climits> #include <deque> #include <iostream> #include <list> #include <limits> #include <map> #include <queue> #include <set> #include <stack> #include <vector> #define ll long long #define MIN(a, b) a < b ? a : b #define MAX(a, b) a > b ? a : b using namespace std; int readline(char *str) { int i = 0; char ch; while((ch = getchar()) != '\n') { str[i++] = ch; } str[i] = '\0'; return i; } int main(int argc, char *argv[]) { int n, k; scanf("%d%d", &n, &k); int * arr = (int *) calloc(n + 1, sizeof(int)); for(int i = 1 ; i <= n; i++) { scanf("%d", &arr[i]); } int count = 0; int book_page_numer = 0; for(int i = 1 ; i <= n; i++) { int chapter_pages = arr[i] / k + (arr[i] % k ? 1 : 0); // cout << "Chapter " << i << " has " << chapter_pages << " pages" << endl; for(int page_num = 1; page_num <= chapter_pages; page_num++) { book_page_numer ++; int prob_num = ((page_num - 1) * k) + 1; int prob_last = page_num * k; // cout << "Page Number: " << page_num << " has probs from " << prob_num << " to " << prob_last << endl; while(prob_num <= prob_last && prob_num <= arr[i]) { if(book_page_numer == prob_num) { // cout << "Book Page number: " << book_page_numer<< endl; count++; } prob_num++; } } } printf("%d\n", count); free(arr); return 0; }