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  1. #include <bits/stdc++.h>
  2. using namespace std;
  3.  
  4. int main() {
  5. 	int n;
  6. 	cin>>n;
  7.  
  8. 	vector<int> numbers(n);
  9.  
  10. 	for(auto& number: numbers){
  11. 		cin>>number;
  12. 	}
  13.  
  14. 	vector<int> maxPrefixSum(n), maxSuffixSum(n);
  15.  
  16. 	int currentSum = 0;
  17.  
  18. 	for(int i=0; i<n; i++){
  19. 		currentSum = max(0,max(numbers[i],currentSum+numbers[i]));
  20. 		maxPrefixSum[i] = currentSum;
  21. 	}
  22.  
  23. 	currentSum = 0;
  24.  
  25. 	for(int i=n-1; i>=0; i--){
  26. 		currentSum = max(0, max(numbers[i], currentSum + numbers[i]));
  27. 		maxSuffixSum[i] = currentSum;
  28. 	}
  29.  
  30. 	vector<int> maxPrefixAcc(n), maxSuffixAcc(n);
  31.  
  32. 	int current = INT_MIN;
  33.  
  34. 	for(int i=0; i<n; i++){
  35. 		current = max(current, maxPrefixSum[i]);
  36. 		maxPrefixAcc[i] = current;
  37. 	}
  38.  
  39. 	current = INT_MIN;
  40.  
  41. 	for(int i=n-1; i>=0; i--){
  42. 		current = max(current, maxSuffixSum[i]);
  43. 		maxSuffixAcc[i] = current;
  44. 	}
  45.  
  46. 	int answer = INT_MIN;
  47.  
  48. 	for(int i=0; i<n-1; i++){
  49. 		int sum = maxPrefixAcc[i] + maxSuffixAcc[i+1];
  50. 		answer = max(answer,sum);
  51. 	}
  52.  
  53. 	cout<<answer;
  54.  
  55. 	return 0;
  56. }
Success #stdin #stdout 0.01s 5316KB
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https://ideone.com/DfOxvG
language:
C++14 (gcc 8.3)
created:
1 day ago
visibility:
public

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