KS1 (AUG 19 Division B)

1 
#include "bits/stdc++.h"
using namespace std;

typedef unsigned long long ull;
typedef long long ll;

#define mod 1e9+7
#define eps 1e-9 

#define mp make_pair
#define pb push_back 

int main()
{
ios_base :: sync_with_stdio(false);
cin.tie(NULL);
cout.tie(NULL);

#ifndef ONLINE_JUDGE
freopen("input.txt","r",stdin);
freopen("output.txt","w",stdout);
freopen("error.txt","w",stderr);
#endif 

ll t,n;
cin >> t;

while(t--)
{
    vector<ll> varr[1000001];
    cin >> n; vector<ll> num(n);
    for(int i=0 ; i<n ; ++i) cin >> num[i];
    
    ll xr=0,ans=0; varr[0].pb(-1);

    for(int i=0 ; i<n ; ++i) { xr = xr^num[i]; varr[xr].pb(i); }
    
    for(int i=0 ; i<1000001 ; ++i) 
    {
        //if(varr[i].size()) cerr << i << " " << varr[i].size() << endl;
        for(int j=0 ; j<varr[i].size() ; ++j)
        {
            ans += j*varr[i][j] - (varr[i].size()-1-j)*varr[i][j];  
        }
        ans -= varr[i].size()*(varr[i].size()-1)/2;
    }
    cout << ans << endl; 

}

return 0;
}

This is giving WA on some subtasks. I read the editorial and tried to implement it on my own. (using 0-based indexing) . Any hints where I am lacking would be helpful?
Off - Topic :
Also for some reason, this programs fails to read/write from txt files (had to use online IDEs) while using on Sublime Text 3 while others work fine. Any help regarding this would also be appreciated.
Thanks :slight_smile:

2

Please either format your code or (better!) link to your submission - the forum software has mangled it and it won’t compile! :slight_smile:

Edit:

vector<ll> varr[1000001];

This is likely to cause problems - why are you allocating 1000001 vectors on the stack?

2 Likes
3

I formatted the code. Also how does declaring it globally helps? (I did declare it globally, and now it works on sublime. Still WA in some subtasks.)

4

It seems that the static area of memory in Codechef’s Online Judge is larger than the stack.

Link to this solution?

2 Likes
5

It got accepted. Thanks. Just forgot to reset the vector array for each test case after declaring it globally. Thanks again.

Link to the AC

1 Like