Tomi-3-0

#include <stdio.h>
#include <cs50.h> // to get plain text
#include <string.h> // for strlen()
#include <ctype.h> // for string operation upper, lower

void Do_substitute(); // for further substitute
void alpha_arr_val(char pos, string key);
// to get the alphabet array value of each plain text element (ex:plaintext = h|alphabet array = 8 {a=0, b=1 .....z=26})

int main(int argc, string argv[])