P9569 "NnOI R2-T1" Khronostasis Katharsis

There are $n$ balloons tied to a flat ground. Their initial height is $0$ meters, and the initial time is the $0$-th second. After the rope of a balloon is cut, it will rise at a constant speed. The $i$-th balloon rises $v_i$ meters per second. Now it is known that the rope of the $i$-th balloon will be cut at the $t_i$-th second. Find the index of the balloon with the greatest height at the $T$-th second; if there are multiple, output the smallest index among them.

The first line contains two integers $n, T$. The next $n$ lines: the $i$-th line contains two integers $v_i, t_i$.

Output one integer in one line, representing the answer.

**[Sample 1 Explanation]** At the $10$-th second, the heights of the five balloons are $9, 14, 9, 30, 21$ meters, respectively. **[Constraints]** For $100\%$ of the testdata, it is guaranteed that $1 \le n, v_i \le 10^5$, and $0 \le t_i \le T \le 10^4$. **Hint: This problem enables bundled tests.** $$ \def\r{\cr\hline} \def\None{\text{None}} \def\arraystretch{1.5} \begin{array}{c|c|c} \textbf{Subtask} & \textbf{Sp. Constraints} & \textbf{Score}\r \textsf1& n \le 1000 & 33 \r \textsf2& v_i\ 相等 & 10 \r \textsf3& t_i \ 相等 & 10 \r \textsf4& 无特殊限制 & 47 \r \end{array} $$ ### Source |Item|Person| |:-:|:-:| |idea|EstasTonne| |data|EstasTonne| |check|Chuanjiang Mowang| |solution|EstasTonne| Translated by ChatGPT 5