if-else statement in c++

If block contains the condition, if condition is true, then the statements of if block will execute and if the condition is false then the statement of else block will execute.

Syntax :

if(boolean_expression) {
   /* statement(s) will execute if the boolean expression is true */
} else {
   /* statement(s) will execute if the boolean expression is false */
}               

Block Diagram :

Example:

#include<iostream>
int main(){
// local variable declaration:
  int x;
  cout<< "Enter any number :";
  cin>>x;
  // check the  condition
  if( x >= 0 ) {
/* if condition is true then print the following */

    cout<<"Number is Positive";
   }
   else
   {
     cout<<"Number is Negative";
   }
  return 0;
}                    
                

Enter any number: 12
Number is Positive

Enter any number: -12
Number is Negative

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