func_code_string: #include <bits/stdc++.h>   using namespace std;   const int MOD = 1000000007;   long long POW(long long a, long long b, long long MMM = MOD) {     long long ret = 1;     for (; b; b >>= 1, a = (a * a) % MMM)       if (b & 1) ret = (ret * a) % MMM;     return ret;   }   long long gcd(long long a, long long b) { return b ? gcd(b, a % b) : a; }   long long lcm(long long a, long long b) {     if (a == 0 || b == 0) return a + b;     return a * (b / gcd(a, b));   }   int dx[] = {0, 1, 0, -1, 1, 1, -1, -1}, dy[] = {1, 0, -1, 0, 1, -1, 1, -1};   int ddx[] = {-1, -2, 1, -2, 2, -1, 2, 1}, ddy[] = {-2, -1, -2, 1, -1, 2, 1, 2};   pair<int, int> a[200000];   int c[20], b[200000];   int n;   bool ok(int k) {     for (int(i) = (0); (i) <= (n - 1); (i) += (1))       a[i] = make_pair(b[i] >= (1 << k) ? 0 : b[i], i);     for (int(i) = (k - 1); (i) >= (0); (i) -= (1)) {       int t = max_element(a, a + n) - a;       swap(a[0], a[t]);       if (a[0].first == 0) return 0;       if (31 - __builtin_clz(a[0].first) != i) return 0;       c[i] = b[a[0].second];       for (int(j) = (n - 1); (j) >= (0); (j) -= (1))         if (a[j].first & (1 << i)) a[j].first ^= a[0].first;     }     printf( %d n , k);     int now = 0;     for (int(i) = (1); (i) <= (1 << k); (i) += (1)) {       printf( %d  , now);       now ^= (c[__builtin_ctz(i)]);     }     return 1;   }   int main() {     scanf( %d , &n);     for (int(i) = (0); (i) <= (n - 1); (i) += (1)) {       scanf( %d , &b[i]);     }     for (int(k) = (18); (k) >= (1); (k) -= (1)) {       if (ok(k)) return 0;     }     puts( 0 n0 );   }   