P3378 [Template] Heap

Given a sequence that is initially empty, support the following three operations: 1. Given an integer $x$, insert $x$ into the sequence. 2. Output the smallest number in the sequence. 3. Delete the smallest number in the sequence (if multiple numbers are smallest, delete only $1$).

The first line contains an integer $n$ representing the number of operations. Then follow $n$ lines, each describing one operation. Each line first contains an integer $op$ indicating the operation type. - If $op = 1$, then an integer $x$ follows, meaning to insert $x$ into the sequence. - If $op = 2$, it means to output the smallest number in the sequence. - If $op = 3$, it means to delete the smallest number in the sequence. If multiple numbers are smallest, delete only $1$.

For each operation $2$, output one line with one integer representing the answer.

**Constraints** - For $30\%$ of the testdata, it is guaranteed that $n \leq 15$. - For $70\%$ of the testdata, it is guaranteed that $n \leq 10^4$. - For $100\%$ of the testdata, it is guaranteed that $1 \leq n \leq 10^6$, $1 \leq x \lt 2^{31}$, $op \in \{1, 2, 3\}$. Translated by ChatGPT 5