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  1. #include <iostream>
  2. #include <vector>
  3.  
  4. int main() {
  5. 	int unsorted[] = {5,7,12,890,-5,-4,3,2,1,56,890,-1043};
  6. 	std::vector<bool> tracker(12, false);
  7. 	const int n = 5; //we want the top n largest numbers
  8. 	std::vector<int> topN;
  9.  
  10. 	for(int i = 0; i < n; i++) {
  11. 		//an integer needs to store the maximum in the list.
  12. 		//but it cannot be one that has already been marked
  13. 		//as true in tracker.
  14. 		//so first we will loop until the first un-marked number.
  15. 		int unmarked_index = 0;
  16. 		for(; unmarked_index < tracker.size(); unmarked_index++) {
  17. 			if(!tracker[unmarked_index]) {
  18. 				//we found one that has not been visited yet
  19. 				break;
  20. 			}
  21. 		}
  22. 		//the max variable will hold the maximum after the next
  23. 		//loop finishes.  first we must initialize it
  24. 		//and the loop we just came from gives us the
  25. 		//index to initialize with.
  26. 		//also, we must keep track of where the max is found
  27. 		//so that it can be marked in tracker after the loop
  28. 		int max = unsorted[unmarked_index];
  29. 		int max_index = unmarked_index;
  30. 		for(int j = unmarked_index+1; j < tracker.size(); j++) {
  31. 			if(!tracker[j] && unsorted[j] > max) {
  32. 				//if j is not marked and j is > max
  33. 				max = unsorted[j];
  34. 				max_index = j;
  35. 			}
  36. 		}
  37. 		//time to mark max as used
  38. 		tracker[max_index] = true;
  39. 		//and add max to topN
  40. 		topN.push_back(max);
  41. 	}
  42.  
  43. 	for(int i = 0; i < topN.size(); i++) {
  44. 		std::cout << topN[i];
  45. 		if(i != topN.size() - 1) std::cout << ", ";
  46. 	}
  47. 	std::cout << std::endl;
  48.  
  49. 	return 0;
  50. }
Success #stdin #stdout 0s 3228KB
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Standard input is empty
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890, 890, 56, 12, 7
https://ideone.com/kO4hVv
language:
C++ (gcc 8.3)
created:
9 years ago
visibility:
public

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