The first day of C language learning

C language

First, the goal

A) SRS---analysis-Draw Flowchart---Code

b) give you a procedure. Can understand the implementation process. Write execution results

c) Develop a good coding habit---code before you need to stare

Pave the mat for performance tests and lay the groundwork for learning other languages later. Increase the depth of the test

Note: No basic---more practice; basic---depth/help

Second, the course arrangement

A) First day

I. What is the procedure

Ii. Composition of the program

III. process-oriented programming ideas

Iv. definition and use of functions

b) the next day

I. Algorithm---branch of the program

II. algorithm---Cycle of the program

c) The third day

I. Other data structures of the program

1. Arrays

2. Structural body

II. Design analysis of shopping system

First day

I. The history of language

Ii. Composition of the procedure

program = data structure + algorithm

function = input/output + processing logic

Data:

1 + 1 = 2 fixed, known--- constant

x + y = z change, unknown--- variable

X1+x2+x3+......= y changes. Unknown, a set of the same type--- array

Name, age, salary different types, multiple groups, unknown--- structure of the change

Data type:

int---integer (integer), Float---float (6 decimal places), char---character type (alphabetic, numeric, kanji)

Double---dual precision (12 decimal places)

Algorithm:

Order

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Branch

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Cycle

Three, process-oriented programming ideas

Example: Finding the sum of two integers

Analysis:

1. Identify data structures and types

Data structure: input---Two variables; output: A variable

Data type: int

2. Determine the algorithm

Order

3. Draw a flowchart

4. Copy the text in the flowchart into the code template as a gaze. Translate the gaze into code

Single Gaze--// multi-line gaze--*/* XXX */

Code Template:

1, Program Description: Description of the program to achieve the function

2. header file: #include <stdio.h>

<stdio.h> standard input and output header file, you need to use some functions in the header file, so you need to load the program in advance

<string.h> String Header File

3, function declaration (own definition function need):

4, the main function of the implementation: Voidmain ()

5, the implementation of their own definition functions:

1. Define variables:

I

The first day of C language learning