/* * FASCINATING NUMBER VERIFICATION https://www.sololearn.com/post/62174/?ref=app * INPUT SPECIFICATION (CODE PLAYGROUND) Enter a positive number to check, having at least 3 digits. Or enter a range to check, in the following format: Example: To check for Fascinating numbers between 100 and 1000 (inclusive), use this range: 100 1000 © 2019 SoloLearn Community */ #include #include // Define whether calculation details // are shown on screen. For checking wide // range, this better be 0 to avoid TLE : ) #define VERBOSE_MODE 1 // Display extra information of a fascinating // number, e.g. the 3 products of the number, // and the merged digits formed from the // digits in the 3 products. void show_details(int n) { // We only accept positive numbers having // at least 3 digits, anything less will be // considered unfit. if(n < 100) return; // Product array of long long p[3] = {n, n * 2LL, n * 3LL}; // Digits from the product array above // will be merged in . // NOTE: Digit zero will be excluded. long long merged = 0; // This section of code merges all unique // digits from the product array of for(int i = 0; i < 3; ++i) { long long t = p[i]; // * // Count number of digits in int digits = 1; for(long long x = t; x /= 10; ++digits); // Used to divide to extract digits int div = (int)pow(10, digits - 1); // Repeat while not equal zero // Here we will extract digits of // from first digit to the last while(t) { // Get the digit and store in int q = t / div; // We will not merge digit 0 (zero) if(q) merged = merged * 10 + q; // Subtract by ( *
) t -= (q * div); // Divide
by 10 div /= 10; } } // Print the products and merged digits // NOTE: %I64d is a format specifier for // signed 64bit integer (Non standard) printf(" Products: [%lld, %lld, %lld]\n", p[0], p[1], p[2]); printf(" Digits: %lld\n", merged); } // Verifies whether a number is a // fascinating number. int is_fascinating(int n) { // We only accept positive numbers having // at least 3 digits, anything less will be // considered unfit. if(n < 100) return 0; // is used to mark the presence of a // digit. int flag = 0; for(int i = 1, bit, r; i < 4; ++i) { // Product of times long long p = n * i; // Repeat while
not equals to zero // Here we will extract the digits from // the last digit to first. while(p) { // Get the digit and store in r = p % 10; // Divide
by 10 for next digit extraction p /= 10; // We will exclude digit 0 (zero) if(!r) continue; // is 2 raised to the power of // digit . bit = 1 << r; // We check if was set in ; // if it is, the digit had appeared // before, in that case, it is not // fascinating number. if(flag & bit) // digit appears more than once return 0; // Set in flag |= bit; } } // At this point, if value equals // to 0x3fe then is fascinating number. // Otherwise, it is not. if(flag == 0x3fe) return 1; return 0; } int main() { int n1 = 0, n2 = 0, nums; // Read input. // If scanf() failed to extract any value // show input specification (in bad_input) nums = scanf("%d %d", &n1, &n2); if(nums < 1) goto bad_input; if(1 == nums) { // We have 1 input; check if it is a // fascinating number. printf("Your number: %d\n", n1); if(is_fascinating(n1)) { puts(" It's a fascinating number."); // Details are always shown when // checking for a single number show_details(n1); printf("\n"); } else { puts(" It's not a fascinating number.\n"); } } else if(2 == nums) { // We have 2 inputs; assume as a range of // values to check. // General range and range start check if(n1 > n2 || n1 < 100) goto bad_input; int count = 0, r = 0, c = 0; puts("Checking for fascinating numbers"); printf("Between %d and %d\n\n", n1, n2); for(int i = n1; i <= n2; ++i) { if(is_fascinating(i)) { ++count; // increase result counter if(VERBOSE_MODE) // show details ? { printf("%d. %d\n", count, i); show_details(i); // Group results by five rows if(++r % 5) continue; printf("\n"); } else { printf("%-10d ", i); // Group results by 3 column if(++c % 3) continue; // Group results by five rows printf((++r % 5 ? "\n" : "\n\n")); } } } // Print summary if(!count) { puts("No fascinating number was found"); } else { if((r % 5) || count < 3) printf((c && (c % 3)) ? "\n\n" : "\n"); printf("Found %d fascinating numbers.\n", count); } } return 0; // Shows input specification for when or if // we have invalid input bad_input: puts("Enter positive integer, having at least 3 digits."); puts("Or enter a range, in the following form:\n \n"); return 0; }