Submission

Score: 100

User: tull

Problemset: ปริมาตรน้ำท่วม

Language: python

Time: 0.012 second

Submitted On: 2026-07-30 20:53:29

n=int(input())
a=list(map(int,input().split()))
MX=2e9
hl=[0 for i in range(n+2)]
hr=[0 for i in range(n+2)]
for i in range(2,n+1):
     hl[i]=max(hl[i-1],a[i-2])
     #print(f'{i} {a[i-2]} {hl[i-1]}')
for i in range(n-1,0,-1):
     hr[i]=max(hr[i+1],a[i])
     #print(f'{i} {a[i]} {hr[i+1]}')
     #print(f'{i}')
ans=0
for i in range(2,n):
     ans+=max(0,min(hl[i],hr[i])-a[i-1])
     #print(f'{i} : {hl[i]} {hr[i]} -> {max(0,min(hl[i],hr[i])-a[i-1])}')
print(ans)
'''
6
6 1 3 0 8 2

'''