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Page 1: Jetta - CS50cdn.cs50.net/2015/fall/lectures/4/m/week4m.pdf · Jetta Jetta Sportwagen Beetle Beetle Convertible Audi A3 Golf Golf Sportwagen Passat. if being tested turn full emissions
Page 2: Jetta - CS50cdn.cs50.net/2015/fall/lectures/4/m/week4m.pdf · Jetta Jetta Sportwagen Beetle Beetle Convertible Audi A3 Golf Golf Sportwagen Passat. if being tested turn full emissions
Page 3: Jetta - CS50cdn.cs50.net/2015/fall/lectures/4/m/week4m.pdf · Jetta Jetta Sportwagen Beetle Beetle Convertible Audi A3 Golf Golf Sportwagen Passat. if being tested turn full emissions

Jetta Jetta Sportwagen Beetle Beetle Convertible Audi A3 Golf Golf Sportwagen Passat

Page 4: Jetta - CS50cdn.cs50.net/2015/fall/lectures/4/m/week4m.pdf · Jetta Jetta Sportwagen Beetle Beetle Convertible Audi A3 Golf Golf Sportwagen Passat. if being tested turn full emissions

if being tested turn full emissions controls on else don't

Page 5: Jetta - CS50cdn.cs50.net/2015/fall/lectures/4/m/week4m.pdf · Jetta Jetta Sportwagen Beetle Beetle Convertible Audi A3 Golf Golf Sportwagen Passat. if being tested turn full emissions

if wheels are turning but steering wheel isn't turn full emissions controls on else don't

Page 6: Jetta - CS50cdn.cs50.net/2015/fall/lectures/4/m/week4m.pdf · Jetta Jetta Sportwagen Beetle Beetle Convertible Audi A3 Golf Golf Sportwagen Passat. if being tested turn full emissions
Page 7: Jetta - CS50cdn.cs50.net/2015/fall/lectures/4/m/week4m.pdf · Jetta Jetta Sportwagen Beetle Beetle Convertible Audi A3 Golf Golf Sportwagen Passat. if being tested turn full emissions

reflections on trusting trustTo what extent should one trust a statement that a program is free of Trojan

horses? Perhaps it is more important to trust the people who wrote the software.

Page 8: Jetta - CS50cdn.cs50.net/2015/fall/lectures/4/m/week4m.pdf · Jetta Jetta Sportwagen Beetle Beetle Convertible Audi A3 Golf Golf Sportwagen Passat. if being tested turn full emissions
Page 9: Jetta - CS50cdn.cs50.net/2015/fall/lectures/4/m/week4m.pdf · Jetta Jetta Sportwagen Beetle Beetle Convertible Audi A3 Golf Golf Sportwagen Passat. if being tested turn full emissions

1 pick up phone book 2 open to middle of phone book 3 look at names 4 if "Smith" is among names 5 call Mike 6 else if "Smith" is earlier in book 7 open to middle of left half of book 8 go to line 3 9 else if "Smith" is later in book 10 open to middle of right half of book 11 go to line 3 12 else 13 give up

Page 10: Jetta - CS50cdn.cs50.net/2015/fall/lectures/4/m/week4m.pdf · Jetta Jetta Sportwagen Beetle Beetle Convertible Audi A3 Golf Golf Sportwagen Passat. if being tested turn full emissions

1 pick up phone book 2 open to middle of phone book 3 look at names 4 if "Smith" is among names 5 call Mike 6 else if "Smith" is earlier in book 7 open to middle of left half of book 8 go to line 3 9 else if "Smith" is later in book 10 open to middle of right half of book 11 go to line 3 12 else 13 give up

Page 11: Jetta - CS50cdn.cs50.net/2015/fall/lectures/4/m/week4m.pdf · Jetta Jetta Sportwagen Beetle Beetle Convertible Audi A3 Golf Golf Sportwagen Passat. if being tested turn full emissions

1 pick up phone book 2 open to middle of phone book 3 look at names 4 if "Smith" is among names 5 call Mike 6 else if "Smith" is earlier in book 7 search for Mike in left half of book 8 9 else if "Smith" is later in book 10 search for Mike in right half of book 11 12 else 13 give up

Page 12: Jetta - CS50cdn.cs50.net/2015/fall/lectures/4/m/week4m.pdf · Jetta Jetta Sportwagen Beetle Beetle Convertible Audi A3 Golf Golf Sportwagen Passat. if being tested turn full emissions

on input of n elements if n < 2 return else sort left half of elements sort right half of elements merge sorted halves

Page 13: Jetta - CS50cdn.cs50.net/2015/fall/lectures/4/m/week4m.pdf · Jetta Jetta Sportwagen Beetle Beetle Convertible Audi A3 Golf Golf Sportwagen Passat. if being tested turn full emissions

on input of n elements if n < 2 return else sort left half of elements sort right half of elements merge sorted halves

Page 14: Jetta - CS50cdn.cs50.net/2015/fall/lectures/4/m/week4m.pdf · Jetta Jetta Sportwagen Beetle Beetle Convertible Audi A3 Golf Golf Sportwagen Passat. if being tested turn full emissions

recursion

Page 15: Jetta - CS50cdn.cs50.net/2015/fall/lectures/4/m/week4m.pdf · Jetta Jetta Sportwagen Beetle Beetle Convertible Audi A3 Golf Golf Sportwagen Passat. if being tested turn full emissions

google.com/search?q=recursion

Page 16: Jetta - CS50cdn.cs50.net/2015/fall/lectures/4/m/week4m.pdf · Jetta Jetta Sportwagen Beetle Beetle Convertible Audi A3 Golf Golf Sportwagen Passat. if being tested turn full emissions

partypalooza.com

Page 17: Jetta - CS50cdn.cs50.net/2015/fall/lectures/4/m/week4m.pdf · Jetta Jetta Sportwagen Beetle Beetle Convertible Audi A3 Golf Golf Sportwagen Passat. if being tested turn full emissions

void swap(int a, int b) { int tmp = a; a = b; b = tmp; }

Page 18: Jetta - CS50cdn.cs50.net/2015/fall/lectures/4/m/week4m.pdf · Jetta Jetta Sportwagen Beetle Beetle Convertible Audi A3 Golf Golf Sportwagen Passat. if being tested turn full emissions

environment variables

stack

uninitialized data

initialized data

text

heap

Page 19: Jetta - CS50cdn.cs50.net/2015/fall/lectures/4/m/week4m.pdf · Jetta Jetta Sportwagen Beetle Beetle Convertible Audi A3 Golf Golf Sportwagen Passat. if being tested turn full emissions

GDB

Page 20: Jetta - CS50cdn.cs50.net/2015/fall/lectures/4/m/week4m.pdf · Jetta Jetta Sportwagen Beetle Beetle Convertible Audi A3 Golf Golf Sportwagen Passat. if being tested turn full emissions

string

Page 21: Jetta - CS50cdn.cs50.net/2015/fall/lectures/4/m/week4m.pdf · Jetta Jetta Sportwagen Beetle Beetle Convertible Audi A3 Golf Golf Sportwagen Passat. if being tested turn full emissions
Page 22: Jetta - CS50cdn.cs50.net/2015/fall/lectures/4/m/week4m.pdf · Jetta Jetta Sportwagen Beetle Beetle Convertible Audi A3 Golf Golf Sportwagen Passat. if being tested turn full emissions

char*

Page 23: Jetta - CS50cdn.cs50.net/2015/fall/lectures/4/m/week4m.pdf · Jetta Jetta Sportwagen Beetle Beetle Convertible Audi A3 Golf Golf Sportwagen Passat. if being tested turn full emissions