Python杨辉三角算法详解编程语言

#!/usr/bin/env python 
# -*- coding: utf-8 -*- 
def triangles(): 
      n = 1 
      aboveList = [] 
      while True: 
          if n == 1: 
              aboveList = [1] 
              n = n + 1 
              yield [1] 
          if n == 2: 
              aboveList = [1,1] 
              n = n + 1 
              yield [1,1] 
          newList = [] 
          for x in getMiddleList(aboveList): 
              newList.append(x) 
          newList.insert(0,1) 
          newList.append(1) 
          aboveList = newList 
          n = n + 1 
          yield newList 
      return 'done' 
 
def getMiddleList(aboveList): 
    newList = [] 
    leftNodeVal=0  
    n=1 
    for x in aboveList: 
        if n == 1: 
            leftNodeVal = x 
        else: 
            newList.append(x+leftNodeVal) 
            leftNodeVal = x 
        n += 1 
    return newList 
 
n=0 
for t in triangles(): 
    print(t) 
    n = n + 1 
    if n == 10: 
        break

#!/usr/bin/env python 
# -*- coding: utf-8 -*- 
def triangles(): 
    l = [1,0] 
    while True: 
        yield l[0:-1] 
        l[1:-1] = [l[i-1]+l[i] for i in range(1, len(l))] 
 
n=0 
for t in triangles(): 
    print(t) 
    n = n + 1 
    if n == 10: 
        break