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Need help with small issue on simple begginner decoding program

Aheming2 (2)
Any help can be appreciated. The code is supposed to decode a string for example "!^&*" should output to "abcd". Right now it just decodes the first letter like this "a^&*". I feel like this is because it is defined as a char and not a string however it gives me error if i change it up. Any idea on how i can modify this to work? Thanks in advance :)

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

int main() {
    const int setNum = 26;
    vector<char> normalV(setNum);
    vector<char> cipherV(setNum);
    string toDec = "";
    string beenDec = "";
    int i = 0;

    normalV.at(i) = 'a'; cipherV.at(i) = '!'; ++i;
    normalV.at(i) = 'b'; cipherV.at(i) = '^'; ++i;
    normalV.at(i) = 'c'; cipherV.at(i) = '&'; ++i;
    normalV.at(i) = 'd'; cipherV.at(i) = '*'; ++i;
    normalV.at(i) = 'e'; cipherV.at(i) = '@'; ++i;
    normalV.at(i) = 'f'; cipherV.at(i) = '('; ++i;
    normalV.at(i) = 'g'; cipherV.at(i) = ')'; ++i;
    normalV.at(i) = 'h'; cipherV.at(i) = '-'; ++i;
    normalV.at(i) = 'i'; cipherV.at(i) = '#'; ++i;
    normalV.at(i) = 'j'; cipherV.at(i) = '_'; ++i;
    normalV.at(i) = 'k'; cipherV.at(i) = '='; ++i;
    normalV.at(i) = 'l'; cipherV.at(i) = '+'; ++i;
    normalV.at(i) = 'm'; cipherV.at(i) = '['; ++i;
    normalV.at(i) = 'n'; cipherV.at(i) = '{'; ++i;
    normalV.at(i) = 'o'; cipherV.at(i) = '$'; ++i;
    normalV.at(i) = 'p'; cipherV.at(i) = ']'; ++i;
    normalV.at(i) = 'q'; cipherV.at(i) = '}'; ++i;
    normalV.at(i) = 'r'; cipherV.at(i) = ';'; ++i;
    normalV.at(i) = 's'; cipherV.at(i) = ':'; ++i;
    normalV.at(i) = 't'; cipherV.at(i) = ','; ++i;
    normalV.at(i) = 'u'; cipherV.at(i) = '%'; ++i;
    normalV.at(i) = 'v'; cipherV.at(i) = '<'; ++i;
    normalV.at(i) = 'w'; cipherV.at(i) = '.'; ++i;
    normalV.at(i) = 'x'; cipherV.at(i) = '>'; ++i;
    normalV.at(i) = 'y'; cipherV.at(i) = '/'; ++i;
    normalV.at(i) = 'z'; cipherV.at(i) = '?'; ++i;

    // User inputs message
    do {
        cout << "Enter a secret message: ";
        getline(cin, toDec);
    } while (toDec.length() == 0);

    beenDec = toDec;

    //decodes user's message
    for (i = 0; i < setNum; ++i){
    if (toDec.at(0) == cipherV.at(i)) {
            beenDec.at(0) = normalV.at(i);
        }
    }

    //diplays decoded message
    cout << "Decrypted message: " << beenDec << endl;

    //command drive to stay open
    cin.get();
    cin.get();
    return 0;
}
pnoid (138)
On lines 51 and 52 change the zeros to i. I didn't run it to see if this works, but the zeros mean it only ever checks the first character.
jlb (4973)
You should also consider a loop or use initialization mechanics instead of all those normal.at() lines.
Aheming2 (2)
I changed all of the zeros to i's on lines 51,52 and it caused an out of range memory allocation error to be thrown. Any other ideas?
pnoid (138)
I changed all of the zeros to i's on lines 51,52 and it caused an out of range memory allocation error to be thrown. Any other ideas?


Oh, right, I missed that. If your string is less than 26 characters it will be an out of bounds error in that loop. So you need to use a nested for loop with the outside loop being the length of the string to be decoded and the inside loop being the number of possible characters to check against, or setNum. So basically lines 50-54 are going to be your inside loop with the zeros changed to the iterated int from the outside loop you have to create. Does that make sense? I ran it and that will work.
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