Making program so that if statement is assigned proper number - c++

Question

I'm trying to making it so that if the planet name is not found in the array, it will set the code variable to -1, but it seems to always make the variable -1 regardless. If I don't have the else statement, the program works fine, but then the switch's default statement doesn't work. How do I make it so that the code variable gets assign the proper value if the planet name is entered incorrectly.
#include "stdafx.h"
#include <iostream>
#include <string>
#include <algorithm>
using namespace std;
int main()
{
//declare arrays
string planetNames[8] = { "MERCURY", "VENUS", "EARTH", "MARS", "JUPITER", "SATURN", "URANUS", "NEPTUNE" };
double gravity[8] = { 0.37, 0.78, 1, 0.38, 2.64, 1.16, 1.07, 1.21 };
//declare variable
string name = " ";
double weight = 0.0;
string planet = " ";
double finalWeight = 0.0;
int code = 0;
//explain program to user
cout << "In this program you will enter your first and last name, then your weight, and finally the planet that you want to know your weight on" << endl << endl;
//get input
cout << "What is your first and last name: ";
getline(cin, name);
cout << "How much do you weigh: ";
cin >> weight;
cout << "Which planet would you like to know how much you weigh on: ";
cin >> planet;
//capitalize planet name
transform(planet.begin(), planet.end(), planet.begin(), toupper);
while (weight != -1)
{
for (int x = 0; x < 8; x++)
{
if (planet == planetNames[x])
code = x; //THIS IS WHERE THE PROBLEM IS!!!!!!!!!
else
code = -1;
//end if
}//end for
//calculate and display weights
switch (code)
{
case 0:
finalWeight = weight * gravity[code];
cout << "The weight of " << name << " on " << planetNames[code] << " would be " << finalWeight << "lbs" << endl;
break;
case 1:
finalWeight = weight * gravity[code];
cout << "The weight of " << name << " on " << planetNames[code] << " would be " << finalWeight << "lbs" << endl;
break;
case 2:
finalWeight = weight * gravity[code];
cout << "The weight of " << name << " on " << planetNames[code] << " would be " << finalWeight << "lbs" << endl;
break;
case 3:
finalWeight = weight * gravity[code];
cout << "The weight of " << name << " on " << planetNames[code] << " would be " << finalWeight << "lbs" << endl;
break;
case 4:
finalWeight = weight * gravity[code];
cout << "The weight of " << name << " on " << planetNames[code] << " would be " << finalWeight << "lbs" << endl;
break;
case 5:
finalWeight = weight * gravity[code];
cout << "The weight of " << name << " on " << planetNames[code] << " would be " << finalWeight << "lbs" << endl;
break;
case 6:
finalWeight = weight * gravity[code];
cout << "The weight of " << name << " on " << planetNames[code] << " would be " << finalWeight << "lbs" << endl;
break;
case 7:
finalWeight = weight * gravity[code];
cout << "The weight of " << name << " on " << planetNames[code] << " would be " << finalWeight << "lbs" << endl;
break;
default:
cout << "Invalid planet name" << endl;
}//end switch
cout << endl;
cout << "How much do you weigh(-1 to end the program): ";
cin >> weight;
cout << "Which planet would you like to know how much you weigh on: ";
cin >> planet;
transform(planet.begin(), planet.end(), planet.begin(), toupper);
}//end while
system("pause");
return 0;
}

Answer 1

You need to break the loop after you have found the matching planet name, otherwise the loop keeps searching, and the next name won't match so code is set to -1.
Also: for efficiency and clarity: set code = -1 before the loop and only set to x on a match:
code = -1;
for (int x = 0; x < 8; x++)
{
if (planet == planetNames[x])
{
code = x; //THIS IS WHERE THE PROBLEM IS!!!!!!!!!
break; // And now it's gone ;-)
}
}

Answer 2

this if is fine.
for example if you type mars, code will get value 3.
But then in next step of loop you will set it again to -1 ;)
Break the loop when result is found.
Advice:
Split this part of code to new function.