python判斷

            
              a = 2
b = 1
if a > b:
    print(a)
else:
    print(b)

多個(gè)if語(yǔ)句
a = 2
b = 1
if a > b:
    print(a)
elif a == b:
    print(b)
elif a < b:
    print(a)

三元表達(dá)式
print(a if a > b else b) #打印a如果a大于b的話，否則打印b
            
          

循環(huán)

            
              有2種方式，for x in list,tutle，另一種是while循環(huán)

打印1到100的整數(shù)和
sum = 0
for i in range(1, 101):
    sum += i
print(sum)

sum = 0
i = 0
while i < 101:
    sum += i
    i += 1
print(sum)

break和continue，break是跳出當(dāng)前循環(huán)，而continue是跳過(guò)本次循環(huán)，開(kāi)啟下一次循環(huán)
sum = 0
i = 0
while i < 101:
    if i % 2 == 0: #跳過(guò)偶數(shù)，求出奇數(shù)和
        i += 1
        continue
    else:
        sum += i
        i += 1

print(sum)

sum = 0
i = 0
while i < 101:
    if i % 2 == 0:
        i += 1
        break
    else:
        sum += i
        i += 1
print("i的值為:", i) #最后i的值是1
print(sum)