最大上升子序列和

while 1:
    try:
        n=int(input())
        kk=list(map(int,input().split(" ")))
        l=[0]*n
        for i in range(n):
            mm=0
            for j in range(i):
                if kk[j]<kk[i]:
                    mm=max(l[j],mm)
            l[i]=mm+kk[i]
        print(max(l))
    except:
        break