The document discusses different programming languages and how a C++ program is translated. It describes: 1. There are three main types of programming languages: machine language, assembly language, and high-level languages like C++. 2. A C++ program is first written in a source code file, then compiled into an object file containing machine code. 3. The object file is linked with library files and other object modules to create an executable file that can be run on a computer.

1. The University of Dodoma
High level programming Languages

2. Programming Language
There are three Programming languages
Machine Language
Assembly Language
High level Language

3. 3
Low level PL
(Machine Language)
These a Binary coded instructions
The fundamental language of the computer’s
processor, also called Low Level Language.
All programs are converted into machine
language before they can be executed.
Consists of combination of 0’s and 1’s that
represent high and low electrical voltage.

4. 4
Assembly Language
these are Symbolic coded instructions
A low level language that is similar to machine language.
Uses symbolic operation code to represent the machine operation
code.
Many assembly languages exist, one for each processor.
Despite differences, many assembly languages share the same
fundamental structure.

5. 5
High Level Language
Computer (programming) languages
that are easier to learn.
Uses English like statements.
Examples are C ++, Visual Basic,
,Java ,Pascal, Fortran and …....

6. Programming Language Generations
First Generation
(late 1940s):
Machine-level
programming languages
 Fast and efficient, executed
directly on the CPU
 Consists only of 0s and 1s
 Difficult for humans to read,
write, and debug

7. Programming Language Generations
Second Generation
(early 1950s):
 Symbolic assemblers
 Interpreting routines
 Very early compilers
Assembly languages
 Simple mnemonic instructions <opcode> <operands>
 Assembler translates into machine code
 Handcoding in assembly only for low-level needs

8. Programming Language Generations
Third Generation
(mid 1950s - present):
High level, general-purpose
 FORTRAN, LISP, COBOL, ALGOL
(Ada, Basic, C, C++, Java, Pascal, Smalltalk, …)
 Easier for humans to read, write, debug
 Compiler translates into machine code before
running
 Interpreter translates into machine code at
runtime

9. Programming Language Generations
Fourth Generation (1970s - ):
Specification languages, query languages, report
generators, systems engineering
 Maple, Mathematica, Postscript, SPSS, SQL
Fifth Generation (1980s - ):
Solve problems using constraints rather than
algorithms, used in Artificial Intelligence
 Prolog

10. Translating a C++ program
University of Dodoma-cive 10

11. Creating a source file
It is important to use the correct file extension depends on the
compiler you use, the most commonly found file extensiosare .cpp
and .cc.
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12. Explanations
1.First, a text editor is used to save the C++
program in a text file. In other words,the
source code is saved to a source file.
2.The source file is put through a compiler for
translation. If everything works as planned, an
object file made up of machine code is
created. The object file is also referred to as a
module.
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13. Compilers
Compilers is a program that translate high-level language to
machine language
The compiler on your system converts
source code to object code.
 Source code
 the original program in a high level language
 Object code
 the translated version in machine language

14. 8-14
Compilers ……
Figure 8.1 Compilation process

15. 8-15
Interpreters
Interpreter: a translating program and executes the
statements in sequence
 Unlike an assembler or compiler which produce machine
code as output, which is then executed in a separate step
 An interpreter translates a statement and then immediately
executes the statement
 Interpreters can be viewed as simulators

16. Chapter 17 Programming Tools 17-16
Linkers
Searches program libraries to find library
routines used by the program
 Library: collection of pre-written functions and
subroutines made available to perform commonly
required activities
Determines the memory locations that code
from each module will occupy and relocates
instructions by adjusting absolute references
Resolves references among files

17. Finally, the linker combines the object file with other
modules to form an executable
file. These further modules contain functions from
standard libraries or
parts of the program that have been compiled
previously.
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18. Transformation of a high-level
language into machine …..
18

19. Contents of a program
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20. Pre-processor Directives
Preprocessing
 Occurs before a program is compiled
 Inclusion of other files
 Definition of symbolic constants and macros
 Conditional compilation of program code
 Conditional execution of preprocessor directives
Format of preprocessor directives
 Lines begin with #
 Only whitespace characters before directives on a line

21. 13.2 The #include Preprocessor
Directive#include
 Copy of a specified file included in place of the directive
#include <filename> -
 Searches standard library for file
 Use for standard library files
#include "filename"
 Searches current directory, then standard library
 Use for user-defined files
Used for
 Loading header files (#include <iostream>)
 Programs with multiple source files to be compiled together
 Header file - has common declarations and definitions (classes,
structures, function prototypes)
 #include statement in each file