python list 固定位置添加元素,删除元素

a = [[1,1],[2,2],[3,3],[4,4],[5,5],[6,6],[7,7],[8,8],[9,9],[10,10]]

b = [3,4,5,6] #需要删除和替换元素所在位置

c = [[99,99],[100,100]]  #等带添加的元素




for i in range(len(c)):

    a[b[i]] = c[i]


start = len(c)

j = 0
for i in range(start,len(b)):
	

    print(b[i]-j)
    del a[b[i]-j]

    j = j + 1

print(a)