Score : $800$ points
Takahashi and Aoki will take $N$ exams numbered $1$ to $N$. They have decided to compete in these exams. The winner will be determined as follows:
For each exam $i$, Takahashi decides its importance $c_i$, which must be an integer between $l_i$ and $u_i$ (inclusive).
Let $A$ be $\sum_{i=1}^{N} c_i \times$ (Takahashi's score on Exam $i$), and $B$ be $\sum_{i=1}^{N} c_i \times$ (Aoki's score on Exam $i$). Takahashi wins if $A \geq B$, and Aoki wins if $A < B$.
Takahashi knows that Aoki will score $b_i$ on Exam $i$, with his supernatural power.
Takahashi himself, on the other hand, will score $0$ on all the exams without studying more. For each hour of study, he can increase his score on some exam by $1$. (He can only study for an integer number of hours.) However, he cannot score more than $X$ on an exam, since the perfect score for all the exams is $X$.
Print the minimum number of study hours required for Takahashi to win.
Input is given from Standard Input in the following format:
$N$ $X$ $b_1$ $l_1$ $u_1$ $b_2$ $l_2$ $u_2$ $:$ $b_N$ $l_N$ $u_N$
Print the minimum number of study hours required for Takahashi to win.
2 100 85 2 3 60 1 1
115
One optimal strategy is as follows:
Choose $c_1 = 3, c_2 = 1$.
Study to score $100$ on Exam $1$ and $15$ on Exam $2$.
Then, $A = 3 \times 100 + 1 \times 15 = 315$, $B = 3 \times 85 + 1 \times 60 = 315$ and Takahashi will win.
2 100 85 2 3 60 10 10
77
1 100000 31415 2718 2818
31415
10 1000 451 4593 6263 324 310 6991 378 1431 7068 71 1757 9218 204 3676 4328 840 6221 9080 684 1545 8511 709 5467 8674 862 6504 9835 283 4965 9980
2540