fork download
copy 
  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.  
  27.  
  28. int bruteforce(int n, int k1, int k2){
  29. 	int ans = 0;
  30.  
  31. 	for(int i=0; i<n-2; i++){
  32. 		for(int j=i+1; j<n-2; j++){
  33. 			int leftSum = a[i] + a[j];
  34. 			if(leftSum <= k1) continue;
  35.  
  36. 			for(int k=j+1; k<n-1; k++){
  37. 				for(int l=k+1; l<n; l++){
  38. 					int rightSum = a[k] + a[l];
  39. 					if(rightSum > k2 ) ans++;
  40. 				}
  41. 			}
  42. 		}
  43. 	}
  44. 	return ans;
  45. }
  46.  
  47.  
  48.  
  49.  
  50. //* Global 2 ptr * local 2 ptr 
  51.  
  52. //* O(  n * O(1) ) + O(n*logn)  == O(n*logn)
  53. int consistency1(int n, int k1, int k2) {
  54.  
  55. 	int ans = 0;
  56.  
  57. 	vector<int> pairsInSuffix(n);
  58.  
  59. 	for(int i=n-2; i>=0; i--){
  60.  
  61. 		int t = k2-a[i];
  62. 		int j = upper_bound(a.begin()+i+1 , a.end(), t) - a.begin();
  63.  
  64. 		int pairsFormedByCurr = n-j;
  65. 		pairsInSuffix[i] =  pairsFormedByCurr + pairsInSuffix[i+1];
  66.  
  67. 	}
  68.  
  69. 	for(int j=n-3, i=0; j>=1; j--){
  70. 		int left = 0;
  71. 		while(i<j && a[i]+a[j] <= k1) i++;
  72. 		if(i==j) break;
  73. 		left += j-i;
  74.  
  75. 		int right = pairsInSuffix[j+1];
  76.  
  77. 		ans += (left * right);
  78.  
  79. 	}
  80.  
  81. 	return ans;
  82.  
  83. }
  84.  
  85.  
  86.  
  87.  
  88.  
  89. //* O( n * (O(logn) + O(1) )  + O(n*logn) == O(n*logn)
  90. int consistency2(int n, int k1, int k2) {
  91.  
  92. 	int ans = 0;
  93.  
  94. 	vector<int> pairsBy(n);
  95. 	for(int i=0; i<n-1; i++){
  96. 		int j = upper_bound(a.begin()+i+1, a.end(), k2-a[i]) - a.begin();
  97.  
  98. 		pairsBy[i] = n-j;
  99. 	}
  100.  
  101. 	vector<int> pairsInSuffix(n);
  102. 	for(int i=n-2; i>=0; i--){
  103. 		pairsInSuffix[i] = pairsInSuffix[i+1] + pairsBy[i];
  104. 	}
  105.  
  106. 	for(int j=1; j<n-2; j++){
  107. 		int i = upper_bound(a.begin(), a.begin() + j, k1-a[j]) - a.begin();
  108. 		int left= j-i;
  109.  
  110. 		int right = pairsInSuffix[j+1];
  111.  
  112. 		ans += left*right;
  113. 	}
  114.  
  115. 	return ans;
  116. }
  117.  
  118.  
  119.  
  120.  
  121.  
  122.  
  123.  
  124.  
  125.  
  126.  
  127.  
  128.  
  129.  
  130.  
  131.  
  132.  
  133.  
  134.  
  135.  
  136. int practice(int n, int k1, int k2) {
  137.  
  138. 	return 0;
  139.  
  140. }
  141.  
  142.  
  143. void solve() {
  144.  
  145. 	int n, k1, k2;
  146. 	cin >> n >> k1 >> k2;
  147.  
  148. 	a.resize(n);
  149. 	for(int i=0; i<n; i++) cin >> a[i];
  150.  
  151.     cout << bruteforce(n, k1, k2) << " ";
  152.     cout << consistency1(n, k1, k2) << " ";
  153.     cout << consistency2(n, k1, k2) << endl;
  154.  
  155.  
  156.     // cout << bruteforce(n, k1, k2) << " -> ";
  157.     // cout << practice(n, k1, k2) << endl;
  158.  
  159. }
  160.  
  161.  
  162.  
  163.  
  164.  
  165. int32_t main() {
  166.     ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
  167.  
  168.     int t = 1;
  169.     cin >> t;
  170.     while (t--) {
  171.         solve();
  172.     }
  173.  
  174.     return 0;
  175. }
Success #stdin #stdout 0.01s 5328KB
comments (?)
stdin
copy 
4
8 9 7
1 2 3 4 5 6 8 12
6 1 3
0 1 1 1 2 2
6 1 3
1 1 1 1 2 2
6 3 3
1 2 2 2 2 3
stdout
copy 
2 2 2
2 -> 0
3 3 3
3 -> 0
6 6 6
6 -> 0
5 5 5
5 -> 0
https://ideone.com/LgbE78
language:
C++14 (gcc 8.3)
created:
3 days ago
visibility:
public

Share or Embed source code

Discover > Sphere Engine API

The brand new service which powers Ideone!

Discover > IDE Widget

Widget for compiling and running the source code in a web browser!