oj.uz

Submission #359141

# Submission time Handle Problem Language Result Execution time Memory
359141 2021-01-26T11:37:44 Z ogibogi2004 XOR Sum (info1cup17_xorsum) C++14
77 / 100
 1600 ms 25972 KB 
#include<bits/stdc++.h>
using namespace std;
#define ll long long
const ll MAXN=1e6+6;
const ll logN=30;
ll n,ans;
ll a[MAXN];
int main()
{
	ios_base::sync_with_stdio(false);
	cin.tie(NULL);
	cout.tie(NULL);
	cin>>n;
	for(int i=1;i<=n;++i)
	{
		cin>>a[i];
	}
	int ans=0;
	for(int j=0;j<logN;++j)
	{
		vector<int>a1;
		if(j!=0)
		{
			for(int i=1;i<=n;++i)
			{
				if(!(a[i]&(1<<(j-1))))
				{
					a1.push_back(a[i]);
				}
			}
			for(int i=1;i<=n;++i)
			{
				if(a[i]&(1<<(j-1)))
				{
					a1.push_back(a[i]);
				}
			}
			for(int i=0;i<a1.size();++i)a[i+1]=a1[i];
		}
		ll cnt0up=0,cnt1up=0,cnt0down=0,cnt1down=0;
		int p=n;
		ll cnt=0;
		for(int i=1;i<=n;++i)
		{
			if(a[i]&(1<<j))++cnt1up;
			else ++cnt0up;
		}
		for(int i=1;i<=n;++i)
		{
			while(p>0&&a[p]%(1<<j)+a[i]%(1<<j)>=(1<<j))
			{
				if(a[p]&(1<<j))++cnt1down,--cnt1up;
				else ++cnt0down,--cnt0up;
				--p;
			}
			if(a[i]&(1<<j))
			{
				cnt+=cnt0up+cnt1down;
			}
			else
			{
				cnt+=cnt1up+cnt0down;
			}
			if((2*a[i])&(1<<j))++cnt;
		}
		//cout<<j<<" "<<cnt<<endl;
		if((cnt/2)%2==1)
		{
			ans+=(1<<j);
		}
	}
	cout<<ans<<"\n";
return 0;
}

Compilation message

xorsum.cpp: In function 'int main()':
xorsum.cpp:38:17: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   38 |    for(int i=0;i<a1.size();++i)a[i+1]=a1[i];
      |                ~^~~~~~~~~~

Subtask #1
7.0 / 7.0

# Verdict Execution time Memory Grader output
1 Correct 7 ms 364 KB Output is correct
2 Correct 7 ms 364 KB Output is correct

Subtask #2
11.0 / 11.0

# Verdict Execution time Memory Grader output
1 Correct 940 ms 16256 KB Output is correct
2 Correct 908 ms 15856 KB Output is correct

Subtask #3
21.0 / 21.0

# Verdict Execution time Memory Grader output
1 Correct 940 ms 16256 KB Output is correct
2 Correct 908 ms 15856 KB Output is correct
3 Correct 1216 ms 16628 KB Output is correct
4 Correct 1166 ms 16120 KB Output is correct

Subtask #4
38.0 / 38.0

# Verdict Execution time Memory Grader output
1 Correct 7 ms 364 KB Output is correct
2 Correct 7 ms 364 KB Output is correct
3 Correct 162 ms 2116 KB Output is correct
4 Correct 166 ms 2128 KB Output is correct

Subtask #5
0 / 23.0

# Verdict Execution time Memory Grader output
1 Correct 7 ms 364 KB Output is correct
2 Correct 7 ms 364 KB Output is correct
3 Correct 940 ms 16256 KB Output is correct
4 Correct 908 ms 15856 KB Output is correct
5 Correct 1216 ms 16628 KB Output is correct
6 Correct 1166 ms 16120 KB Output is correct
7 Correct 162 ms 2116 KB Output is correct
8 Correct 166 ms 2128 KB Output is correct
9 Correct 1600 ms 16408 KB Output is correct
10 Execution timed out 1615 ms 25972 KB Time limit exceeded
11 Halted 0 ms 0 KB -