Submission #258599

#	Time	Username	Problem	Language	Result	Execution time	Memory
258599		IOrtroiii	Swap (BOI16_swap)	C++14	100 / 100	62 ms	5628 KiB

swap

#include <bits/stdc++.h>

using namespace std;

const int MX = 400400;

int N;
int A[MX];
int state[MX];
int ans[MX];

int query(int i) {
   int ans = MX;
   for (; i > 0; i /= 2) {
      if (state[i] != 1) ans = min(ans, A[i]);
      if (state[i] == 0) return ans;
      if (i % 2 && state[i - 1] != 0) {
         ans = min(ans, A[i - 1]);
         if (state[i - 1] == 1) return ans;
      }
   }
}

void modify(int i, int val) {
   for (; i > 0; i /= 2) {
      if (A[i] == val) {
         state[i] = 0;
         return;
      }
      if (i % 2) {
         if (A[i - 1] == val) {
            state[i] = state[i - 1] = 1;
            return;
         } else state[i - 1] = 0;
      }
      state[i] = 1;
   }
}

int main() {
   ios_base::sync_with_stdio(false); cin.tie(nullptr);
   cin >> N;
   for (int i = 1; i <= N; ++i) cin >> A[i];
   for (int i = N + 1; i <= 2 * N + 1; ++i) A[i] = MX;
   state[1] = 0; for (int i = 2; i <= 2 * N + 1; ++i) state[i] = -1;
   for (int i = 1; i <= N; ++i) {
      int val = query(i);
      ans[i] = min({val, A[i * 2], A[i * 2 + 1]});
      if (ans[i] == val) {
         modify(i, val);
         state[i * 2] = 0;
         state[i * 2 + 1] = 0;
      } else if (ans[i] == A[i * 2]) {
         state[i * 2] = 1;
         state[i * 2 + 1] = 0;
      } else {
         assert(ans[i] == A[i * 2 + 1]);
         state[i * 2 + 1] = 1;
      }
   }
   for (int i = 1; i <= N; ++i) cout << ans[i] << ' '; cout << '\n';
   return 0;
}

Compilation message (stderr)

swap.cpp: In function 'int main()':
swap.cpp:61:4: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
    for (int i = 1; i <= N; ++i) cout << ans[i] << ' '; cout << '\n';
    ^~~
swap.cpp:61:56: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
    for (int i = 1; i <= N; ++i) cout << ans[i] << ' '; cout << '\n';
                                                        ^~~~
swap.cpp: In function 'int query(int)':
swap.cpp:22:1: warning: control reaches end of non-void function [-Wreturn-type]
 }
 ^

• Subtask 1: 10 / 10
• Subtask 2: 11 / 11
• Subtask 3: 27 / 27
• Subtask 4: 20 / 20
• Subtask 5: 32 / 32