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Modulo and the way you work in Python

In Zed Shaw Learn the Python Tough Path (pp. 15-16), it has an example exercise

 100 - 25 * 3 % 4

the result is 97 (try it!)

I do not see the order of operations that could do this.

100 - 25 = 75
3% 4 = 0
or (100-25 * 3) = 225% 4 = ??? but in any case not 97 I don’t think ...

A similar example 3 + 2 + 1 - 5 + 4 % 2 - 1 / 4 + 6that gives 7

In what order are operations performed?

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8 answers

: * % -, 25 * 3 % 4. * % , , 25 * 3. 75. 75 % 4, 3. , 100 - 3 - 97.

+22

→ →

In [3]: 25 * 3
Out[3]: 75

In [4]: 75 % 4
Out[4]: 3

In [5]: 100 - 3
Out[5]: 97

, .

+2

, - Zac , 1/4 - , Python 2.X . , , (, float, 0.

3 + 2 + 1 - 5 + 4 % 2 - 1 / 4 + 6
3 + 2 + 1 - 5 + (0) - (0) + 6 
6 - 5 + 6
1 + 6
7
+2

:

'*' '%' , .

  • 25 * 3 = 75
  • 75% 4 = 3 (4 * 18 = 72, 3)
  • 100 - 3 = 97

Q.E.D.

0

: 100 - 25 * 3 % 4

, 25 * 3 75% 4 , .

, % python , x% y x / y. , 75 / 4 18, 3, 100 - 3 = 97.

, .

0

% , *, 3 + 2 + 1-5 + 4% 2-1/4 + 6 = 3 + 2 + 1-5 + (4% 2) - (1/4) + 6 = 1 + (4% 2) - (1/4) +6 = 1 + 0- (1/4) + 6 = 1- (1/4) + 6 = 0,75 + 6 = 6,75, , , , , , - .

0

, , , . , .

75, 4, 18,75

18, 4, 72 ( 3 75)

100-25 * 3% 4 97. PEMDAS, :

#!/bin/python

A = 100
B = 25
C = 3
D = 4
E = B*C # 75
F = E%D # 3
G = A-F # 97
print("B * C ="), E
print("E % D ="), F
print("A - F ="), G

, modulo (%) ,

0

Python evaluates% after *, but before + or _.

So,

(100 - 25 * 3 % 4)
(100 - 75 % 4)
(100 - 3) 
(97)
0
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