Difference between revisions of "C-and-C++/C3/Strings/English-timed"

|Welcome to the spoken-tutorial on Strings in C and C++

|What is a string.  

|Declaration of a string.  

|Initialization of a string.  

| Few examples on string.  

|Ubuntu Operating System version 11.04

| gcc and g++ Compiler version 4.6.1 .

|Let us start with the introduction to strings.  

|String is a sequence of characters, that is treated as a single data item.  

|Size of string = length of string + 1  

|Let me tell you how to declare a string.   

|char, name of string and size  

|char is the data type, name of the string is the string name, and we can give the size here.  

|Eg: here we have declared a character string names with size 10  

|Note that our file name is string.c

|In this program, we will take a string as an input from the user and print it.  

|Here string.h includes the declarations, functions, constants of string handling utilities.  

|Whenever we work on string functions, we should include this header file.  

|This is our main function.  

|Here we are declaring the string strname' with size '30'.  

|Here we are accepting a string from the user.  

|To read a string, we can use scanf() function with format specifier %s

|Then we print the string.  

| And this is our return statement.  

| Now click on Save

| Please open the terminal window by pressing Ctrl, Alt and T keys simultaneously on your keyboard.  

|To compile, type gcc space string.c space -o space str  

|And press Enter  

| To execute, type ./str  

|now press Enter  

|Here it is displayed as Enter the string .  

| I will type Talk To A Teacher.  

|now press Enter.  

|The output is displayed as The string is Talk To A Teacher

|Until now we discussed about the declaration of a string.  

|char var_name[size] = “string”;  

|Eg: Here we have declared a character string "names" with size 10 and the string is "Priya"

|char var_name[ ] = String within single quotes  

|eg: char names[10] = Priya in single quotes  

|First, press shift, ctrl and s keys simultaneously on your keyboard  

|Now save the file with the name stringinitialize

|Now click on Save

| We are going to initialize the string.  

| = and within the double quotes “Spoken- Tutorial”;  

|Now, click on Save  

|Now remove these two lines, as we are only going to print the string.  

|Click on Save.  

|Come back to our terminal.  

|gcc space stringinitialize.c space -o space str2  

|Here we have str2 because we don't want to overwrite the output parameter str for the file string.c

|Now press Enter.  

|To execute, type ./str2  

|The output is displayed as "The string is Spoken-Tutorial".

|Suppose here we type the spelling of string as sting

|Now click on Save.

|Come back to our terminal

|sting.h: no such file or directory  

|compilation terminated  

|This is because the compiler is not able to find the header file with the name sting.h  

|Type r here.  

|Now click on Save.  

|Come back to our terminal.  

|Wide character array initialized from non-wide string  

|format %s expects argument of type 'char, ' but  argument 2 has type 'int'  

|This is because we used %s as the format specifier for string.

|And we are initializing it with an integer data type

|Type char here.  

|Click on Save.  

|Let us execute. Come back to our terminal.

|Now we will see how to execute the same program in C++

|Let me open our file string.c

|First, press shift, ctrl and S key simultaneously on your keyboard.  

|Now save the file with an extension .cpp

|and click on Save.  

|Now we will change the header file as iostream.  

|Include the using statement.  

|Now click on Save.  

|And will declare a string variable.

|Type string space strname and a semicolon

|Click on Save.  

| Replace the printf statement with the cout statement.   

|Delete the scanf statement and type getline opening bracket closing bracket within the brackets type(cin, strname)  

|At the end, type a semicolon.  

|Now again, replace the printf statement with the cout statement.  

|Delete the format specifier and \n  

|Now delete the comma  

|Type two opening angle brackets and within the double quotes type \n  

|And click on Save

|Here we have declared a string variable 'strname'

|Since we do not use the format specifier in C++, the compiler should know that strname is a string variable.  

|Here we use getline to extract the characters from the input sequence.  

|It stores them as a string.  

|g++ space string.cpp space -o space str3  

|and press Enter.  

|To execute, type ./str3  

|Press Enter.  

|It is displayed as Enter the string

|I will enter as Talk To A Teacher  

|Now press Enter  

|"The string is Talk To A Teacher"  

|Strings  

|Declaration of a string  

|eg: char strname[30]  

|Initialization of a string  

|eg: char strname[30] = “Talk To A Teacher”

|Write a program to print a string using the 2nd syntax