1. Formatted output uses string concatenation to form a template: This leads to formatted output: (Personal business Card making) use of formatted output: The% placeholder S is the character, and D represents the number%s%d%r??? The first format: (Must be one-to-one) the second format: (no one by one correspondence) Note: Formatted output, in the formatted output, the simple representation of% need to use percent of 2.while......else ... (The specific scene will be used) when the while loop is not interrupted by break, then go elsecount = 0while count <=5:count + = 1print (' Loop ', count) else:print (' This cycle is over! ') when the while loop is interrupted by break, then do not go Elsecount = 0while True:count + = 1print (' Loop ', count) if Count = = 5:breakelse:print (' This cycle has ended! ') 3. Operator logical operator (new knowledge point) and with or or not is not the first case: the logical operators are before and after the comparison operation (first priority) Priority concept: () > Not > and > or, the same priority is calculated from left to right 4 True 5 flase 6 Flase The second case: the logical operators are numbers before and after (the same priority is computed from left to right) x or Y if x true, return x, else yx and y if x True, return y, Else X (and and or opposite Other people's ideas:and= with 0 get 0 back to the right of or = or or 1 to 1 Returns the conversion of the Left ( and > or ) number to a Boolean (new knowledge point) int--------->bool not 0 true 0 falsebool---------->int True 1,flase 0 print (1>2 and 3 or 4)----------------the >4 logical operator operation, look first and or not, The process of summarizing the rules of operations from left to right based on priority comparison is as follows: Print (1 > 2 and 3 or 4) #4print (3 and1 > 2 or 4) #4print (4 and 3 or 1 > 2) #34. Encode the first spy war film: Drop drop level 01010101 computer file storage, and the transmission of the file 0101010 the primary password in the computer: ASCII (English, numeric and special characters only) ASCII code is: binary with the character of the comparison table is the leftmost 0 reason is to reserve a bit, in case of eight bits equal to a byte 8bit=1byte a byte to represent a character (character: the smallest unit that makes up the content for example: China-----> ' In ' is a character, ' Country ' is a character a------->65a------->97: Unicode Initial creation is 16-bit two bytes representing one character after the upgrade of 32 bits, four bytes representing one character The disadvantage is that the resource waste is re-upgraded to Unicode----------->utf-8,utf-16 (at least 16 bits for one character) UTF-8: a minimum of eight digits to denote a character letter denoted by a byte (8 bits), The European writings with two bytes go to represent (16 bits), in which the Asiatic writings with three bytes go to represent (24-bit) GBK: National standard letters with one byte to express (8 bits), Chinese with two bytes to represent (16 bit) unit conversion: 1BYTE=8BIT1KB=1024B1MB=1024KB1GB =1024mb1tb=1024gb day3 Dictation code: The conversion relationship between BIT,BYTES,KB,MB,GB,TB. UNICODE,UTF-8,GBK, each encoded in English, Chinese, respectively, in a few bytes.
Python Full stack development day02
