feat(codeforces/937): a-f

codeforces/937/f.cc

@@ -0,0 +1,73 @@
+#include <bits/stdc++.h>  // {{{
+
+// https://codeforces.com/blog/entry/96344
+
+#pragma GCC optimize("O2,unroll-loops")
+#pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt")
+
+using namespace std;
+
+using i32 = int32_t;
+using u32 = uint32_t;
+using i64 = int64_t;
+using u64 = uint64_t;
+using f64 = double;
+using f128 = long double;
+//  }}}
+
+void solve() {
+  u64 a, b, c;
+  cin >> a >> b >> c;
+
+  u64 depth = 0;
+  u64 to_take = 1;
+
+  // NOTE :look at prev wrong submissions; full tree assumptions, when u can
+  // have b on last layer this should be oe of ur first observatoins
+  while (to_take && (a > 0 || b > 0 || c > 0)) {
+    ++depth;
+    u64 next_to_take = 0;
+
+    auto take = min(a, to_take);
+    a -= take;
+    next_to_take = 2 * take;
+    to_take -= take;
+
+    take = min(b, to_take);
+    b -= take;
+    to_take -= take;
+    next_to_take += take;
+
+    take = min(c, to_take);
+    c -= take;
+    to_take -= take;
+
+    if (to_take != 0) {
+      cout << -1 << '\n';
+      return;
+    }
+
+    to_take = next_to_take;
+  }
+
+  if (to_take > 0 || a > 0 || b > 0 || c > 0) {
+    cout << -1 << '\n';
+  } else {
+    cout << depth - 1 << '\n';
+  }
+}
+
+int main() {  // {{{
+  cin.tie(nullptr)->sync_with_stdio(false);
+  cin.exceptions(cin.failbit);
+
+  int tc = 1;
+  cin >> tc;
+
+  for (int t = 0; t < tc; ++t) {
+    solve();
+  }
+
+  return 0;
+}
+// }}}