week_1:lecture
Table of Contents
terminology
introduite en semaine 0
- statement (ex: say hello)
- loops (repeat 10)
- boolean expressions (mouse down ?)
- conditions (if, if else)
source code
source code
Source code ? what does it look like ?
CS50 IDE
concepts :
- compiler : a general term for a piece of software that take source code and produces object code from it ( source code → compiler → object code )
- object code : fancy term for 0 and 1
scratch -> C
Intéressant : après avoir montré scratch et fait utiliser, montrer l'équivalence en code source en C. Ce qui permet de limiter l'abstraction.
Aussi :
Le style d'écriture utilisé pour le cours des curly braces est celui-ci :
smthg
{
//code
}
et non :
smthg {
// code
}
Peut-être que le style original est plus clair.
hello world
when green flag clicked → say hellow world“ équivaut en C à :
int main(void) {
printf("hello, world\n");
}
fonctions
say hello, world
printf("hello, world\n");
loops
forever → say hello world
while (true) {
printf("hello, world\n");
}
repeat 10 → say hello world
for (int i = 0; i < 10; i++) {
printf("hello, world\n");
}
variables
set counter to 0 → forever → say counter → change counter by 1
int counter = 0;
while (true) {
printf("%i\n", counter);
counter++;
}
boolean expressions
x < y
x < y and y < x
(x < y) <(x < y) && (y < z))
conditions
if x < y -> say x is less than y else if x > y -> say x is greater than y else -> say x is equal to y
if (x < y) {
printf("x is less than y\n");
} else if {
printf("x is greater than y\n");
} else {
printf("x is equal to y\n");
}
...
#include <stdio.h>
int main(void) { // (parameter/input)
printf("hello, world\n"); // statement
}
previously : CS50 virtual machine with CS50 environment (linux) : make sure everyone have the same environment
now : cloud9 CS50 IDE
cloud : on someone else computer
week_1/lecture.txt · Last modified: 2016/08/20 22:10 by leo