Dark Horse Programmer---iOS learning log 2

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iOS Development Basics-C language

OBJECT-C abbreviation OC, is the extension C of the face object programming language.

C Language Development: BCPL language--b language--c language

C Language Development Status: C language in the computer programming language ranked first

Difficulties in C language learning:

1, Operator: self-increment, decrement operator

2, into the system: all kinds of conversion, source code, anti-code, complement

3. Arrays: one-dimensional arrays, two-bit arrays, multidimensional arrays

4. Loops: nesting, sorting, finding of multiple loops

5, Function: recursive function, recursive call

6, Pointers: first-level pointers, multi-level pointers, pointers and arrays, functions, structure of the relationship between the body

7, Memory management: C language Memory management problems, memory leaks, wild pointers

8. Macros and conditional compilation

9, Multi-file development: Multi-file compilation, multi-file development

How to make a program of C language

1, C language, the program is composed of functions, each function has its own function

2, a program has and only one main function

3, if a program does not have a main function, then this program does not have the ability to run

4, the function is only when the call will be executed, the main function is called by the system

5, the main function of the writing format must follow the specification

How to do the main function:

int main ()

{

Statement

}

C Language Source program analysis

#include <stdio.h>//indicates printf is the function in the stdio.h file

int main () {//int represents the return value of the main function

Main is the name of the main function

() represents the parameters of the main function, if nothing in parentheses means no arguments

printf ("Hello World");

{} indicates that this is a function question

return 0;//printf is a function that is a system-provided function that outputs characters to the console

\ n means line break at output.

return 0; Indicates that the main function returns to the system a 0

}

C-Language execution process

1. Write the source file

(compile)----. the target file of the O suffix---(link). Out suffix executable file----start execution

Dark Horse Programmer---iOS learning log 2