AtCoder Beginner Contest 139 C - Lower
from itertools import groupby N=int(input()) h=list(map(int,input().split())) g=[] for i,j in enumerate(h): if i==0: pass else: if h[i]-h[i-1]>0: g.append(False) else: g.append(True) ans=0 for k,g in groupby(g): if k==True: moji=len(list(g)) ans=max(ans,moji) print(ans)