2020牛客寒假算法基础集训营4 D.子段异或

#include <bits/stdc++.h>
 
#define debug(x) cerr<<#x<<'='<<x<<endl
#define set0(x) memset(x,0,sizeof(x))
using namespace std;
typedef long long ll;
typedef pair<ll,ll> pii;
template<typename T> void read(T &x){
    x = 0;char ch = getchar();ll f = 1;
    while(!isdigit(ch)){if(ch == '-')f*=-1;ch=getchar();}
    while(isdigit(ch)){x = x*10+ch-48;ch=getchar();}x*=f;
}
 
ll n,a[200010],ans = 0;
map<ll,int> Mp;
int main() {
    read(n);
    ll csu = 0;
    Mp[0] = 1;
    for(int i=0;i<n;i++){
        read(a[i]);
        csu^=a[i];
        ans+=Mp[csu];
        Mp[csu]+=1;
    }
    cout<<ans<<endl;
    return 0;
}