Submission #247016

#	Time	Username	Problem	Language	Result	Execution time	Memory
247016		ernestvw	Arranging Shoes (IOI19_shoes)	C++17	65 / 100	1084 ms	20856 KiB

shoes

    #include <bits/stdc++.h>
    using namespace std;
     
    using ll = long long;
     
    ll subtask3(vector<int> S) {
    	int n = (int)S.size();
    	ll ans = 0;
    	return ans;
    }
     
    ll subtask4(vector<int> S) {
    	int n = (int)S.size();
    	ll ans = 0;
    	for(int i = 0; i < n/2; ++i) {
    		ans += (ll)i;
    	}
    	return ans;
    }
     
    ll count_swaps(vector<int> S) {
    	int n = (int)S.size();
    	ll ans = 0;
    	vector<bool> prise(n, false);
     
    	bool sub3 = false;
    	for(int i : S) if(abs(i) != abs(S[0])) sub3 = false;
    	if(sub3) return subtask3(S);
     
    	bool sub4 = true;
    	for(int i = 0; i < n / 2; ++i)
    		if(S[i] > 0 || S[i + n/2] < 0 || -S[i] != S[i + n/2])
    			sub4 = false;
    	if(sub4) return subtask4(S);
     
    	vector<set<int>> L(n+1), R(n+1);
    	int i = 0;
    	while(i < n) {
    		if(S[i] < 0) {
    			int j = -1;
    			for(int k = i + 1; k < n; ++k) if(S[k] == -S[i]) {
    				j = k;
    				break;
    			}
    			for(int l = j; l > i + 1; --l)
    				swap(S[l], S[l-1]), ++ans;
    		}
    		else {
    			if(i > 0 && S[i-1] == -S[i]) {
    				++i;
    				continue;
    			}
    			int j = -1;
    			for(int k = i + 1; k < n; ++k) if(S[k] == -S[i]) {
    				j = k;
    				break;
    			}
    			for(int l = j; l > i; --l)
    				swap(S[l], S[l-1]), ++ans;			
    		}
    		i++;
    	}
    	return ans;
    }

Compilation message (stderr)

shoes.cpp: In function 'll subtask3(std::vector<int>)':
shoes.cpp:9:10: warning: unused variable 'n' [-Wunused-variable]
      int n = (int)S.size();
          ^

• Subtask 1: 10 / 10
• Subtask 2: 20 / 20
• Subtask 3: 0 / 20
• Subtask 4: 15 / 15
• Subtask 5: 20 / 20
• Subtask 6: 0 / 15