One 、gcc compiler

gcc(CNU Compiler) yes CNU Platform compiler , Can be C、C++ Compile and link the source program into an executable file , Support suffix ：

• .c： C Language source code
• .h: The header file contained in the program
• .i It's pretreated C Source code file
• .s Assembly language code file
• .o Compiled object file

gcc -o hello hello.c

• -o Output the executable
• -c Only require the compiler to output object code （.o file ）, Without outputting the executable
• -g For debugging
• ./hello View output
• -Wall Check Show more warnings

Let's fight
Use vi Write a 123*…*100 The program , And use gcc compile
Let's look at the picture editor .

result ：

Two 、 Program debugging

3、 ... and 、C Language foundation

A program should consist of two parts

• A description of the data ： Formulate the type of data and the organization form of data in the program , Data structure
• A description of the operation ： Operation steps , That is algorithm
  
  The best programming state ：
• 1、 Rational thinking , You can make a flow chart
• 2、 Start editing the code

Let's fight ：
Judge whether the year entered by the user is a leap year

• 1、 Ideas , flow chart

• To judge whether a year is a leap year, two conditions need to be met at the same time
  (1) It can be 4 to be divisible by , Can not be 100 to be divisible by
  (2) It can be 400 to be divisible by
  

• 2、 Code
  
  

Four 、 summary

1、 The code cannot be pasted and needs to be solved ！
2、 Think slowly 、 Sort out a program , It's still very good
3、 My ability cannot be qualitatively improved in a short time , If so, it's the result of accumulation , So take your time , It's better to be down-to-earth .