TERRAFORM

This question accounts for $50\%$ of the total test. Please do not forget to submit your answer, timed out tests will result in $0$ points awarded.

Your family recently bought exoplanet TRAPPIST$1$E from the Annual Planet Auctions and gave a region of the planet to you. To your surprise, the region you were given was a rocky mountain range A of M mountains with heights Hi$...$Hm$.$

You decided to terraform the region to make it look exactly like a mountain range B of M mountains with heights G$|..$G$.$

For mountain range A to look exactly like B$,$ if array H $=$ array G

You have access to an infinite supply of explosives that can reduce the height of any mountain by $1$ per explosion. The bomb can only be dropped in between consecutive mountains, hence both mountains will have their neights decrease by $1$ per explosion.

Determine the minimum number of explosions required to make

mountain range A look exactly like b$,$ or return $-1$ it it's not possible$$CONSTRAINTS$.1=$ M $4=105005=$HA $<=109$

$0<=$ G $<=109$

INPUT SPECIFICATIONS

$*$input$1$: the number of mountains in the mountain range, M

$*$input$2$:$-$ the heights of mountain range A$,$ Hi$...$Hm

$*$input$3$:$-$ the heights of mountain range B$,$ G$|...$Gm

OUTPUT SPECIFICATIONS

$$ output:$-$ integer denoting the minimum number of explosions needed

EXAMPLE

Given

$*$M$=3$

$*$H $=(2,3,21\}$

$*$H $=(2,3,21$

$*$G $=11,1,1\}$

After explosion between Oth and $1$st index,

H $=11,2,2)$

After explosion between $1$st and $2$nd index.

H $=(1,1,1\}$

Now H $=$ G

Therefore the minimum number of explosions required should be

$2.$