1 / 20

Lab 1 – Learning the Debugger

Lab 1 – Learning the Debugger. EECE 351 Spring 2000 Lecture # 3. Lecture & Lab. Control Structures if , else if , else , switch for & while The Debugger Breakpoints Walking through the code Edit and Continue. Introduction. Before we begin, you need to know the following:

hesper
Download Presentation

Lab 1 – Learning the Debugger

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Lab 1 – Learning the Debugger EECE 351 Spring 2000 Lecture # 3 EECE 351 – Lecture 3

  2. Lecture & Lab • Control Structures • if, else if, else, switch • for & while • The Debugger • Breakpoints • Walking through the code • Edit and Continue EECE 351 – Lecture 3

  3. Introduction • Before we begin, you need to know the following: • false is 0. • true is any other number (positive or negative, as long as it isn’t 0). • Usually code happens one line at a time. • Control structures let you change the flow of the code. • Inside conditionals, use “==” not “=” • 90% of the time, do not put a semicolon after! EECE 351 – Lecture 3

  4. Overview Normal Code for / while if and relatives EECE 351 – Lecture 3

  5. Selective • The if keyword allows your program to decide which option to perform. if (/*test*/) { //True, will only do this if test != 0 } EECE 351 – Lecture 3

  6. Selective (cont.) • You can combine if with else to establish a two-option test. if (/*test*/) { //True, will only do this if test != 0 } else //will only do this code if test == 0 EECE 351 – Lecture 3

  7. Selective (cont.) • else if will help make more elaborate tests. if (/*test*/) { //True, will only do this if test != 0 } else if (/*test2*/) { //Will only do this if test == 0 and test2 != 0 } else //Will only do this code if both tests == 0 EECE 351 – Lecture 3

  8. Selective (cont.) • switch is another selective structure. • It is combined with the case keyword to determine which action to perform. • default is used to specify an action to do when none of the other cases are matched. In an SE world, defaults are MANDATORY! • Use break to keep other sections from running. In an SE world, this is the only time you will use breaks! EECE 351 – Lecture 3

  9. Selective (cont.) • Example: switch(/*SomeNumber*/) { case0: //Only do this if SomeNumber == 0 break; case1: //Only do this if SomeNumber == 1 break; default: //Do this all other times. } EECE 351 – Lecture 3

  10. Repetitive • There are two options for the repetitive control structures. • They both perform the same way, but here are some guidelines: • for – only use when you know the amount of repetitions. • while – use when you need something to happen to stop you. (user hits certain key, end of file reached, etc.) EECE 351 – Lecture 3

  11. for • The for loop has three parts: for(int ct = 0; ct < 10; ct++) { //What you want to repeat goes here } Incremention (each) Initialization Segment (once) Test Segment (each) EECE 351 – Lecture 3

  12. For (cont.) • These parts’ positions are not mandatory : int ct = 0; //Initialization for(; ct < 10; ct++) int ct = 0; //Initialization for(; ct < 10;) { ct++; //Incremention } for(;;) //Infinite Loop BAD! EECE 351 – Lecture 3

  13. While • The other repetition structure comes in two variations, while and do/while. • do/while is commonly used when you want to perform your actions once before testing. do { //Your actions go here } while (/*something is true*/); EECE 351 – Lecture 3

  14. While (cont.) • I, however, have never needed a do/while. Neither will you! • You can get by with just a while. • The structure for a while is like this: while(/*This is true*/) { //What you want to do goes here! } EECE 351 – Lecture 3

  15. What we know • Control Structures • Selective • if,else if, else • Repetitive • while, for EECE 351 – Lecture 3

  16. Where we are going • Lecture – Functions • Prototypes • Definitions • Calls EECE 351 – Lecture 3

  17. Lab 1 – The Debugger • I have a project located at “\\engr_asu\ece351\section 1\Labs\Lab1” • Download the project to a local directory. “C:\Temp\YourName\Lab1” • Open the project “*.dsw” • Examine the code. • Place a breakpoint on the line of code with the first “cout” statement (F9). EECE 351 – Lecture 3

  18. Lab 1 – The Debugger (cont.) • Do you have the red dot shown above? • Hit the Go Button (F5)! • What happens when the app starts? • Use F-10 to step line-by-line. • Watch the middle left window change at each line you step on. • When you get to cin >> nInput; switch back to the app and type a number. EECE 351 – Lecture 3

  19. Lab 1 – The Debugger (cont.) • Did the number you typed appear in the variable window? • Keep walking through the code using F-10. • Place the cursor on line: fCPU = (float) clock() - fStart; • Use the Run-To-Cursor command to take you to that point. Don’t forget –1! • Press F-11. What happened? EECE 351 – Lecture 3

  20. Homework # 1 • Use the control structures in class to create a simple calculator. • Prompt user for 2 numbers. • Tell user the following: • Sum • Difference • Power XY: X = 1st #, Y = 2nd # • Divisor and remainder • Repeat until user enters 5,682 for both numbers. EECE 351 – Lecture 3

More Related