n,k,*a=map(int,open(0).read().split());m={0:1};p=A=0
for a in a:p^=a;x,p=min((m.get(k,0),k)for k in[2**k-1^p,p]);A+=x;m[p]=x+1
print(n*-~n//2-A)#include <iostream>
#include <algorithm>
#include <string>
#include <vector>
#include <queue>
#include <set>
#include <map>
#include <functional>
#include <unordered_map>
#include <climits>
#include <unordered_set>
using namespace std;
typedef long long LL;
class CF1054D {
public:
LL solve(const vector<int> &a, int k) {
LL n = a.size();
unordered_map<int, int> xor2cnt;
int mask = (1 << k) - 1;
xor2cnt[0]++;
for (int i = 0, xorSum = 0; i < n; i++) {
xorSum ^= a[i];
int newXorSum = min(xorSum, xorSum ^ mask);
xor2cnt[newXorSum]++;
}
LL ans = (1 + n) * n / 2;
for (auto &ite : xor2cnt) {
ans -= calcZero(ite.second);
}
return ans;
}
LL calcZero(LL cnt) {
LL x = cnt / 2;
LL y = cnt - x;
return x * (x - 1) / 2 + y * (y - 1) / 2;
}
};
int main() {
int n, k;
scanf("%d%d", &n, &k);
vector<int> a(n);
for (int i = 0; i < n; i++) {
scanf("%d", &a[i]);
}
printf("%lld\n", CF1054D().solve(a, k));
return 0;
}
762C - Two strings | 802M - April Fools' Problem (easy) |
577B - Modulo Sum | 1555B - Two Tables |
1686A - Everything Everywhere All But One | 1469B - Red and Blue |
1257B - Magic Stick | 18C - Stripe |
1203B - Equal Rectangles | 1536A - Omkar and Bad Story |
1509A - Average Height | 1506C - Double-ended Strings |
340A - The Wall | 377A - Maze |
500A - New Year Transportation | 908D - New Year and Arbitrary Arrangement |
199A - Hexadecimal's theorem | 519C - A and B and Team Training |
631A - Interview | 961B - Lecture Sleep |
522A - Reposts | 1166D - Cute Sequences |
1176A - Divide it | 1527A - And Then There Were K |
1618E - Singers' Tour | 1560B - Who's Opposite |
182B - Vasya's Calendar | 934A - A Compatible Pair |
1618F - Reverse | 1684C - Column Swapping |