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  1. #include <bits/stdc++.h>
  2. using namespace std;
  3. #define int              long long int
  4. #define double           long double
  5. inline int power(int a, int b) {
  6.     int x = 1;
  7.     while (b) {
  8.         if (b & 1) x *= a;
  9.         a *= a;
  10.         b >>= 1;
  11.     }
  12.     return x;
  13. }
  14.  
  15.  
  16. const int M = 1000000007;
  17. const int N = 3e5+9;
  18. const int INF = 2e9+1;
  19. const int LINF = 2000000000000000001;
  20.  
  21. //_ ***************************** START Below *******************************
  22.  
  23.  
  24.  
  25. vector<int> a;
  26. void consistency(int n) {
  27.  
  28. 	vector<int> prefixMaxiDp(n);
  29. 	vector<int> sufixMaxiDp(n);
  30.  
  31. 	int maxi = -INF;
  32. 	int last = 0;
  33. 	for(int i=0; i<n; i++){
  34. 		int curr = max(last + a[i], a[i]);
  35. 		last = curr;
  36. 		maxi = max(maxi, curr);
  37. 		prefixMaxiDp[i] = maxi;
  38. 	}
  39.  
  40. 	last = 0;
  41. 	maxi = -INF;
  42. 	for(int i=n-1; i>=0; i--){
  43. 		int curr = max(last + a[i], a[i]);
  44. 		last = curr;
  45. 		maxi = max(maxi, curr);
  46. 		sufixMaxiDp[i] = maxi;
  47. 	}
  48.  
  49. 	int ans = -INF;
  50. 	for(int i=0; i<n-1; i++){
  51. 		ans = max(ans, prefixMaxiDp[i] + sufixMaxiDp[i+1]);
  52. 	}
  53.  
  54. 	cout << ans << endl;
  55.  
  56.  
  57. }
  58.  
  59. void solve() {
  60.  
  61. 	int n;
  62. 	cin >> n;
  63. 	a.resize(n);
  64. 	for(int i=0; i<n; i++) cin >> a[i];
  65.     consistency(n) ;
  66.  
  67. }
  68.  
  69.  
  70.  
  71.  
  72.  
  73. int32_t main() {
  74.     ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
  75.  
  76.     int t = 1;
  77.     while (t--) {
  78.         solve();
  79.     }
  80.  
  81.     return 0;
  82. }
Success #stdin #stdout 0.01s 5288KB
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https://ideone.com/RbzDDX
language:
C++14 (gcc 8.3)
created:
4 days ago
visibility:
public

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