names = ['Alice', 'Bob', 'Candy', 'David', 'Ellena']
names.append('Zero')
names.insert(-1, 'Phoebe')
names.insert(-2, 'Gen')
print(names)
names.append('Zero')
names.insert(-1, 'Phoebe')
names.insert(-2, 'Gen')
print(names)
2020-12-06
如果使用old_score = d['Alice'],若不存在Alice会报错
但是old_score = d.get['Alice']就不会,只会返回None
但是old_score = d.get['Alice']就不会,只会返回None
2020-12-04
a=['Jenny','Ellena','Alice','Candy']
b=['David','Hally','Bov','Lsen','Karl']
c=set(a)
c.update(b)
print(c)
b=['David','Hally','Bov','Lsen','Karl']
c=set(a)
c.update(b)
print(c)
2020-12-01
L = [75, 92, 59, 68, 99]
sum=sum(L) #求和
number=len(L) #求个数
print(sum/number) #求平价
sum=sum(L) #求和
number=len(L) #求个数
print(sum/number) #求平价
2020-11-29
d = {
'Alice': 45,
'Bob': 60,
'Candy': 75,
'David': 86,
'Ellena': 49
}
print(d)
w= d.pop('Alice')
print(d)
'Alice': 45,
'Bob': 60,
'Candy': 75,
'David': 86,
'Ellena': 49
}
print(d)
w= d.pop('Alice')
print(d)
2020-11-28
d={
'Alice':45,
'Bob':60,
'Candy':75,
'David':86,
'Ellena':49,
}
wgx=d.get('Alice')
d['Alice']=60
print(d)
print(wgx)
'Alice':45,
'Bob':60,
'Candy':75,
'David':86,
'Ellena':49,
}
wgx=d.get('Alice')
d['Alice']=60
print(d)
print(wgx)
2020-11-28
'Alice':[45],
'Bob':[60],
'Candy':[75],
}
d['Alice']=[45,50,61,66]
d['Bob']=[60,80,61,66]
d['Candy']=[75,88,75,90]
print(d)
'Bob':[60],
'Candy':[75],
}
d['Alice']=[45,50,61,66]
d['Bob']=[60,80,61,66]
d['Candy']=[75,88,75,90]
print(d)
2020-11-28
d = {
'Alice':45,
'Bob':60,
'Candy':75,
'David':86,
'Ellena':49,
}
print(d.get('Alice'))
print(d.get('Bob'))
print(d.get('Candy'))
print(d.get('David'))
print(d.get('Ellena'))
print(d.get('WGX'))
'Alice':45,
'Bob':60,
'Candy':75,
'David':86,
'Ellena':49,
}
print(d.get('Alice'))
print(d.get('Bob'))
print(d.get('Candy'))
print(d.get('David'))
print(d.get('Ellena'))
print(d.get('WGX'))
2020-11-28
def my_abs(x):
if not isinstance(x, int) and not isinstance(x, float):
print('param type error.')
return None
if x >= 0:
return x
else:
return -x
print(my_abs(-55))
if not isinstance(x, int) and not isinstance(x, float):
print('param type error.')
return None
if x >= 0:
return x
else:
return -x
print(my_abs(-55))
2020-11-27