import sys
input = sys.stdin.readline

N=int(input())
Y=list(map(int,input().split()))

H=sorted(set(Y))
DICT={H[i]:i for i in range(len(H))}
DP=[0]*len(H)

for i in range(N):
    #print(DP)
    y=Y[i]
    #print(y)
    NDP=[1<<30]*len(H)
    for j in range(len(H)):
        if y>=H[j]:
            NDP[j]=min(NDP[j],DP[j]+y-H[j])
    for j in range(len(H)):
        if H[j]<y:
            NDP[j]=min(NDP[j],DP[j]+y-H[j])
            NDP[DICT[y]]=min(NDP[DICT[y]],DP[j])
        else:
            NDP[j]=min(NDP[j],DP[j]+H[j]-y)

    DP=NDP

    for i in range(1,len(H)):
        DP[i]=min(DP[i],DP[i-1])

#print(DP)
print(min(DP))