func_code_string: #include <bits/stdc++.h>   using namespace std;   namespace io {   const int __SIZE = (1 << 21) + 1;   char ibuf[__SIZE], *iS, *iT, obuf[__SIZE], *oS = obuf, *oT = oS + __SIZE - 1,                                              __c, qu[55];   int __f, qr, _eof;   inline void flush() { fwrite(obuf, 1, oS - obuf, stdout), oS = obuf; }   inline void gc(char& x) {     x = (iS == iT ? (iT = (iS = ibuf) + fread(ibuf, 1, __SIZE, stdin),                      (iS == iT ? EOF : *iS++))                   : *iS++);   }   inline void pc(char x) {     *oS++ = x;     if (oS == oT) flush();   }   inline void pstr(const char* s) {     int __len = strlen(s);     for (__f = 0; __f < __len; ++__f) pc(s[__f]);   }   inline void gstr(char* s) {     for (__c = (iS == iT ? (iT = (iS = ibuf) + fread(ibuf, 1, __SIZE, stdin),                            (iS == iT ? EOF : *iS++))                          : *iS++);          __c < 32 || __c > 126 || __c ==    ;)       __c = (iS == iT ? (iT = (iS = ibuf) + fread(ibuf, 1, __SIZE, stdin),                          (iS == iT ? EOF : *iS++))                       : *iS++);     for (; __c > 31 && __c < 127 && __c !=    ;          ++s, __c = (iS == iT ? (iT = (iS = ibuf) + fread(ibuf, 1, __SIZE, stdin),                                 (iS == iT ? EOF : *iS++))                               : *iS++))       *s = __c;     *s = 0;   }   template <class I>   inline bool gi(I& x) {     _eof = 0;     for (__f = 1,         __c = (iS == iT ? (iT = (iS = ibuf) + fread(ibuf, 1, __SIZE, stdin),                           (iS == iT ? EOF : *iS++))                         : *iS++);          (__c <  0  || __c >  9 ) && !_eof;          __c = (iS == iT ? (iT = (iS = ibuf) + fread(ibuf, 1, __SIZE, stdin),                            (iS == iT ? EOF : *iS++))                          : *iS++)) {       if (__c ==  - ) __f = -1;       _eof |= __c == EOF;     }     for (x = 0; __c <=  9  && __c >=  0  && !_eof;          __c = (iS == iT ? (iT = (iS = ibuf) + fread(ibuf, 1, __SIZE, stdin),                            (iS == iT ? EOF : *iS++))                          : *iS++))       x = x * 10 + (__c & 15), _eof |= __c == EOF;     x *= __f;     return !_eof;   }   template <class I>   inline void print(I x) {     if (!x) pc( 0 );     if (x < 0) pc( - ), x = -x;     while (x) qu[++qr] = x % 10 +  0 , x /= 10;     while (qr) pc(qu[qr--]);   }   struct Flusher_ {     ~Flusher_() { flush(); }   } io_flusher_;   }  // namespace io   using io::gc;   using io::gi;   using io::gstr;   using io::pc;   using io::print;   using io::pstr;   using ll = long long;   using pii = pair<int, int>;   const int MOD = 1000000007;   ll c[500005];   int p2[500005];   map<ll, vector<pii>> NO;   int bcj[500006], ltk;   void binit() { memset(bcj, -1, sizeof bcj); }   int bget(int i) { return (bcj[i] < 0) ? i : (bcj[i] = bget(bcj[i])); }   void bmerge(int i, int j) {     int ri = bget(i), rj = bget(j);     if (ri == rj) {       return;     }     ltk--;     if (bcj[ri] > bcj[rj]) {       swap(ri, rj);     }     bcj[ri] += bcj[rj];     bcj[rj] = ri;   }   signed main() {     ios_base::sync_with_stdio(false);     cin.tie(0);     int n, m, k;     gi(n), gi(m), gi(k);     for (int i = (1); i < ((n) + 1); i++) gi(c[i]);     p2[0] = 1;     for (int i = (1); i < ((n) + 1); i++) {       p2[i] = 2 * p2[i - 1];       if (p2[i] >= MOD) p2[i] -= MOD;     }     while (m--) {       int u, v;       gi(u), gi(v);       auto& ref = NO[c[u] ^ c[v]];       ref.push_back({u, v});     }     ll notinno = (1ll << k) - NO.size();     ll ans = 1ll * (notinno % MOD) * p2[n] % MOD;     binit();     for (auto& k : NO) {       ltk = n;       for (auto& i : k.second) bmerge(i.first, i.second);       ans += p2[ltk];       for (auto& i : k.second) bcj[i.first] = bcj[i.second] = -1;       if (ans >= MOD) ans -= MOD;     }     print(ans);   }   