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datatype

let us understand datatype declaration statement:-


  • int a,b =5;
  • After seen this type of line compiler understand that it is a data type declaration instruction(statement).
  • The first word of that  instruction is obviously data types. for ex- here it is int.
  • We cannot use more than one data types in one line. 
  • Compiler understand that after data type creating a variable, so a and b are the variable or we say the name of memory location.
  • No. of variable can be created in one line.
  • In our statement variable a hold the value 5 but not in b.
  • b variable also hold a value which is unpredictable known as garbage value
  • so every variable in which value is not assigned hold a garbage value   
  • It is not necessary to initialize a value when variable is declared.int a,b; is a declaration statement other statement except declaration are known as action statement. they come after the declaration not before it is a rule of C.
  • int a,b; a=5,b=10; initialize after declaration


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