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

void encryptMessage(char message[], int rot);

int main() 
{
      // cout << (int)'A' << endl
      //   << (int)'Z' << endl
      //   << (int)'a' << endl
      //   << (int)'z' << endl;
    char message[100000];
    int rotation;
    while (cin >> rotation >> message) {
      encryptMessage(message, rotation);
    }
    return 0;
}

void encryptMessage(char message[], int rot)
{
  int messageLen = strlen(message), charIntVal = 0, newCharIntVal = 0, diff = 0;
  char a = 'a', z = 'z', A = 'A', Z = 'Z', newCharVal;
  int int_a = (int) a, int_z = (int) z;
  int int_A = (int) A, int_Z = (int) Z;
  if (rot == 0) {
    cout << message << endl;
  } else {
    for (int i = 0; i < messageLen; i++) {
      charIntVal = (int) message[i];
      if (rot < 0) {
        newCharIntVal = charIntVal + rot;
        if (charIntVal >= int_a && charIntVal <= int_z && newCharIntVal < int_a) {
          diff =  int_a - newCharIntVal;
          newCharIntVal = int_z - diff;
        } else if (charIntVal >= int_A && charIntVal <= int_Z && newCharIntVal < int_A) {
          diff = int_A - newCharIntVal;
          newCharIntVal = int_Z - diff;
        }
      } else if (rot > 0) {
        newCharIntVal = charIntVal + rot;
        if (charIntVal >= int_a && charIntVal <= int_z && newCharIntVal > int_z) {
          diff = newCharIntVal - int_z;
          newCharIntVal = int_a + diff;
        } else if (charIntVal >= int_A && charIntVal <= int_Z && newCharIntVal > int_Z) {
          diff = newCharIntVal - int_Z;
          newCharIntVal = int_A + diff;
        }
      }
      newCharVal = (char) newCharIntVal;
      // cout << endl << message[i] << " " << charIntVal << ", "
      //     << newCharVal << " " << newCharIntVal << endl;
      cout << newCharVal;
    }
    cout << endl;
  }
}
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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
}