Python中for以及break使用动态效果

第1步

for n in range(2, 6):#n=2
    for x in range(2, n):
        if n % x == 0:
            print(n, 'equals', x, '*', n//x)
            break
    else:
        print(n, 'is a prime number')

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第2步

for n in range(2, 6):#n=2
    for x in range(2, n):#循环结束
        if n % x == 0:
            print(n, 'equals', x, '*', n//x)
            break
    else:
        print(n, 'is a prime number')

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第3步

for n in range(2, 6):#n=2
    for x in range(2, n):
        if n % x == 0:
            print(n, 'equals', x, '*', n//x)
            break
    else:
        print(n, 'is a prime number')

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第4步

for n in range(2, 6):#n=2
    for x in range(2, n):
        if n % x == 0:
            print(n, 'equals', x, '*', n//x)
            break
    else:
        print(n, 'is a prime number')

输出:2 is a prime number

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第5步

for n in range(2, 6):#n=3
    for x in range(2, n):
        if n % x == 0:
            print(n, 'equals', x, '*', n//x)
            break
    else:
        print(n, 'is a prime number')

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第6步

for n in range(2, 6):#n=3
    for x in range(2, n):#x=2
        if n % x == 0:
            print(n, 'equals', x, '*', n//x)
            break
    else:
        print(n, 'is a prime number')

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第7步

for n in range(2, 6):#n=3
    for x in range(2, n):#x=2
        if n % x == 0:#3%2=1,False
            print(n, 'equals', x, '*', n//x)
            break
    else:
        print(n, 'is a prime number')

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第8步

for n in range(2, 6):#n=3
    for x in range(2, n):#循环结束
        if n % x == 0:
            print(n, 'equals', x, '*', n//x)
            break
    else:
        print(n, 'is a prime number')

---

第9步

for n in range(2, 6):#n=3
    for x in range(2, n):
        if n % x == 0:
            print(n, 'equals', x, '*', n//x)
            break
    else:
        print(n, 'is a prime number')

---

第10步

for n in range(2, 6):#n=3
    for x in range(2, n):
        if n % x == 0:
            print(n, 'equals', x, '*', n//x)
            break
    else:
        print(n, 'is a prime number')

输出:3 is a prime number

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第11步

for n in range(2, 6):#n=4
    for x in range(2, n):
        if n % x == 0:
            print(n, 'equals', x, '*', n//x)
            break
    else:
        print(n, 'is a prime number')

---

第12步

for n in range(2, 6):#n=4
    for x in range(2, n):#x=2
        if n % x == 0:
            print(n, 'equals', x, '*', n//x)
            break
    else:
        print(n, 'is a prime number')

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第13步

for n in range(2, 6):#n=4
    for x in range(2, n):#x=2
        if n % x == 0:#4%2=0 ,True
            print(n, 'equals', x, '*', n//x)
            break
    else:
        print(n, 'is a prime number')

---

第14步

for n in range(2, 6):#n=4
    for x in range(2, n):#x=2
        if n % x == 0:
            print(n, 'equals', x, '*', n//x)
            break
    else:
        print(n, 'is a prime number')

输出:4 equals 2 * 2

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第15步

for n in range(2, 6):#n=4
    for x in range(2, n):#x=2
        if n % x == 0:
            print(n, 'equals', x, '*', n//x)
            break
    else:
        print(n, 'is a prime number')

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第16步

for n in range(2, 6):#n=5
    for x in range(2, n):
        if n % x == 0:
            print(n, 'equals', x, '*', n//x)
            break
    else:
        print(n, 'is a prime number')

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第17步

for n in range(2, 6):#n=5
    for x in range(2, n):#x按顺序取值2,3,4
        if n % x == 0:#if条件都判断False
            print(n, 'equals', x, '*', n//x)
            break
    else:
        print(n, 'is a prime number')

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第18步

for n in range(2, 6):#n=5
    for x in range(2, n):#x按顺序取值2,3,4,下一步if条件都判断False
        if n % x == 0:
            print(n, 'equals', x, '*', n//x)
            break
    else:
        print(n, 'is a prime number')
输出:5 is a prime number

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