#include <iostream>
#include <vector>
using namespace std;

// static vector<int> Rearrange(int arr[], int n){
//   vector<int> ans;
//   for(int i =0; i< n; i++){
    
//     if(arr[i]<0){
      
//       // ans.insert(ans.begin()+2*i,arr[i]);
//       cout<<"checkif"<<endl;
//     }
//     else{
//       cout<<"checkelse"<<endl;
//       ans.insert(ans.begin()+((2*i)+1),arr[i]);
//     }
//   }
  
//   return ans;
// }
static void Rearrange(int arr[], int n){
  
  int temp;
  int i =0; 
  
    for(int j =0; j < n-1; j++){
      // if( i <= n){
        if(arr[j]<0){
          // cout<<"i: "<<i<<endl;
          // cout<<"j: "<<j<<endl;
          int k = j;
          if( i == k && i == j){
            continue;
          }
          else{
            // cout<<"k: "<<k<<endl;
            temp = arr[i];
            // cout<<"Temp: "<<temp<<endl;
            arr[i] = arr[j];
            // for(int i =0; i<n; i++){
            //   cout<<arr[i]<<" ";
            // }
            // cout<<endl;
            // cout<<"j: "<<j<<endl;
            
            for(; k>=i+1; k--){
              arr[k] = arr[k-1];
            }
            // cout<<endl;
            // for(int i =0; i<n; i++){
            // cout<<arr[i]<<" ";
            // }
           
            arr[i+1] = temp;
            i = i+2;
            // cout<<"arr[i+1]: "<<arr[i+1]<<endl;
            // for(int i =0; i<n; i++){
            // cout<<arr[i]<<" ";
            // }
          }
        
         
       }
    // cout<<"-------"<<endl;
     
    }
 
}
int main() 
{
  
  int n;
  cin>>n;
  int arr[n];
  cout<<"-----Array1-------"<<endl;
  for(int i =0; i<n; i++){
    cin>>arr[i];
    cout<<arr[i]<<" ";
  }
  // ?vector<int> ans;
  cout<<"\n-----Rearranged-------"<<endl;
  Rearrange(arr,n);
  for(int i =0; i<n; i++){
    cout<<arr[i]<<" ";
  }
  
    return 0;
}
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C++ Online Compiler

Write, Run & Share C++ code online using OneCompiler's C++ online compiler for free. It's one of the robust, feature-rich online compilers for C++ language, running on the latest version 17. Getting started with the OneCompiler's C++ compiler is simple and pretty fast. The editor shows sample boilerplate code when you choose language as C++ and start coding!

Read inputs from stdin

OneCompiler's C++ online compiler supports stdin and users can give inputs to programs using the STDIN textbox under the I/O tab. Following is a sample program which takes name as input and print your name with hello.

#include <iostream>
#include <string>
using namespace std;

int main() 
{
    string name;
    cout << "Enter name:";
    getline (cin, name);
    cout << "Hello " << name;
    return 0;
}

About C++

C++ is a widely used middle-level programming language.

  • Supports different platforms like Windows, various Linux flavours, MacOS etc
  • C++ supports OOPS concepts like Inheritance, Polymorphism, Encapsulation and Abstraction.
  • Case-sensitive
  • C++ is a compiler based language
  • C++ supports structured programming language
  • C++ provides alot of inbuilt functions and also supports dynamic memory allocation.
  • Like C, C++ also allows you to play with memory using Pointers.

Syntax help

Loops

1. If-Else:

When ever you want to perform a set of operations based on a condition If-Else is used.

if(conditional-expression) {
   //code
}
else {
   //code
}

You can also use if-else for nested Ifs and If-Else-If ladder when multiple conditions are to be performed on a single variable.

2. Switch:

Switch is an alternative to If-Else-If ladder.

switch(conditional-expression){    
case value1:    
 // code    
 break;  // optional  
case value2:    
 // code    
 break;  // optional  
......    
    
default:     
 code to be executed when all the above cases are not matched;    
}

3. For:

For loop is used to iterate a set of statements based on a condition.

for(Initialization; Condition; Increment/decrement){  
  //code  
}

4. While:

While is also used to iterate a set of statements based on a condition. Usually while is preferred when number of iterations are not known in advance.

while (condition) {  
// code 
}

5. Do-While:

Do-while is also used to iterate a set of statements based on a condition. It is mostly used when you need to execute the statements atleast once.

do {  
 // code 
} while (condition);

Functions

Function is a sub-routine which contains set of statements. Usually functions are written when multiple calls are required to same set of statements which increases re-usuability and modularity. Function gets run only when it is called.

How to declare a Function:

return_type function_name(parameters);

How to call a Function:

function_name (parameters)

How to define a Function:

return_type function_name(parameters) {  
 // code
}