//LOCKER - Magic of the locker
#include<bits/stdc++.h>
typedef long long ll;
#define M 1000000007
using namespace std;

// binary exponentiation
ll binPow(ll a, ll n) {
	if(n == 0)
		return 1;
	if(n == 1)
		return a%M;
	ll r = binPow(a, n/2);
	if(n % 2 == 0) {
		return (r%M * r%M)%M;
	}
	else 
		return (r%M * r%M * a%M)%M;
}

int main () {
	ll t, n;
	cin >> t;
	while(t--) {
		ll ans, n1;
		cin >> n;
		if(n < 3) {
			cout << n << endl;
			continue;
		}
		// if remainder is 1, say for eg n = 10
		// we might think of choosing the combination: 3, 3, 3, 1
		// but you can notice that 1 in the above combination is not giving us any significant profit
		// as any number multiplied by 1 gives the same number. Rather it would be better if instead of 
		// 3*1 we have 2*2 (notice they'll still have same sum but different products)
		if(n%3 == 1) {
			n1 = (n - 4) / 3;
			ans = 4*binPow(3, n1);
		}
		else if(n%3 == 2){
			n1 = (n - 2) / 3;
			ans = 2*binPow(3, n1);
		}
		else 
			ans = binPow(3, n/3);
		ans %= M;
		cout << ans << endl;
	}
	
}
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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
}