There are $N$ barbecue restaurants along a street. The restaurants are numbered $1$ through $N$ from west to east, and the distance between restaurant $i$ and restaurant $i+1$ is $A_i$.
Joisino has $M$ tickets, numbered $1$ through $M$. Every barbecue restaurant offers barbecue meals in exchange for these tickets. Restaurant $i$ offers a meal of _deliciousness_ $B_{i,j}$ in exchange for ticket $j$. Each ticket can only be used once, but any number of tickets can be used at a restaurant.
Joisino wants to have $M$ barbecue meals by starting from a restaurant of her choice, then repeatedly traveling to another barbecue restaurant and using unused tickets at the restaurant at her current location. Her eventual _happiness_ is calculated by the following formula: "(The total deliciousness of the meals eaten) - (The total distance traveled)". Find her maximum possible eventual happiness.
## Constraints
* All input values are integers.
* $2≤N≤5×10^3$
* $1≤M≤200$
* $1≤A_i≤10^9$
* $1≤B_{i,j}≤10^9$
## Input
The input is given from Standard Input in the following format:
$N$ $M$
$A_1$ $A_2$ $...$ $A_{N-1}$
$B_{1,1}$ $B_{1,2}$ $...$ $B_{1,M}$
$B_{2,1}$ $B_{2,2}$ $...$ $B_{2,M}$
$:$
$B_{N,1}$ $B_{N,2}$ $...$ $B_{N,M}$
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