The purpose of this application is to encrypt an integer number into a text message (string). 

The following replacements of digits should be made in the encryption process: $$0\rightarrow ’a’, 1 \rightarrow ’b’, 2 \rightarrow ’c’, 3 \rightarrow ’d’, 4 \rightarrow ’e’, 5 \rightarrow ’f’, 6 \rightarrow ’g’, 7 \rightarrow ’h’, 8 \rightarrow ’i’, 9 \rightarrow ’j’$$.

  • Write the function $$\texttt{void EnCrypt(int n, char Encr[])}$$ that generates the encrypted value of n in the string Encr (Ex: if n = 1092 then Encr = “bajc”).
  • Write a main program that prompts the user to enter an integer value and print the equivalent encryption string.

Difficulty level
This exercise is mostly suitable for students
#include <stdio.h>
#include <string.h>
void EnCrypt(int n, char Encr[])
{
    int i=0,j;
    char aux;
    while(n)
    {
        Encr[i++]=n%10+'a';
        n/=10;
    }
    Encr[i]='\0';
    j=i-1;
    i=0;
    while(i<j)
    {
        aux=Encr[i];
        Encr[i]=Encr[j];
        Encr[j]=aux;
        i++;
        j--;
    }
}

int main()
{
    char str[100];
    EnCrypt(1092,str);
    printf("%s\n",str);
    return 0;
}

 

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