Vector and for doesn't produce results - c++

Question

I'm working on a simple game (rock, paper, scissors) and I got this problem when I try to populate a vector with using elements of another vector as conditions. The code maybe is more easy to understand:
#include "stdafx.h"
#include "../../Library/std_lib_facilities.h"
// With the fibonacci series I can generate a secret sequence of number
int fib(int n){
if (1 == n || 2 == n) {
return 1;
}
else {
return fib(n - 1) + fib(n - 2);
}
}
// It shows the list of element in a given vector
void showVector(vector<int>myVector, string nameVector) {
cout << "\n\n";
cout << nameVector << " Debug: | ";
for (int i = 1; i < 10; i++) {
cout << myVector[i] << " | ";
}
cout << "\n\n";
}
// String variant
void showVector(vector<string>myVector, string nameVector) {
cout << "\n\n";
cout << nameVector << " Debug: | ";
for (int i = 1; i < 10; i++) {
cout << myVector[i] << " | ";
}
cout << "\n\n";
}
// Generate a sequence of number in a vector
vector<int> generateCode(int input) {
vector<int>myVector;
for (int i = 1; i <= 10; i++) {
myVector.push_back(fib(i + input) % 3);
}
return myVector;
}
int main()
{
// Secret sequence of moves, based on the value (0, 1 or 2) i will show Rock, Paper or Scissor
vector<int>fibSeries;
vector<string>movSeries;
// Initialization and settings
int input = 0;
cout << "Digit an integer to start: ";
while (cin >> input) {
// Check the number to make sure is a valid one (i will implement a check later) and generate the secret code
fibSeries = generateCode(input);
// For each 0 i'll put Rock in the vector, same for 1 ( in this case paper ) and 2 ( scissor )
for (int i = 0; i <= fibSeries.size(); i++) {
if (fibSeries[i] == 0){
movSeries.push_back("Rock");
}
else if (fibSeries[i] == 1) {
movSeries.push_back("Paper");
}
else if (fibSeries[i] == 2) {
movSeries.push_back("Scissor");
}
else {
movSeries.push_back("Rock");
}
}
// Shows the vector graphically, for debug.
showVector(fibSeries, "fibisSeries");
showVector(movSeries, "movSeries");
// So for a combination of 1 - 2 - 0 - 1
// The result should be: Paper - Scissor - Rock - Paper
}
return 0;
}
After i execute the code, i get an (Abort). I don't understand, I'm new to C++ so please forgive me if is a stupid error. And most of the code is complex becouse I have rules to follow, so for example if I didn't study something i can't use it here. I just want to know why the code don't want me to use the for with the vector!

Answer 1

for (int i = 0; i <= fibSeries.size(); i++)
As #Yola mentions, you iterate one element more than you have:
if you have the vector std::vector<char> v = {'a', 'b', 'c'};, the elements can be accessed as:
v[0] (-> 'a')
v[1] (-> 'b')
v[2] (-> 'c')
As a rule, your max index will be length - 1.
for (int i = 0; i <= fibSeries.size(); i++)
iterates from 0 to less then or equal to size(); that is, 0, 1, 2, 3 (4 elements, in a 3 elements vector).
Correct code should be:
for (int i = 0; i < fibSeries.size(); i++)
^^^

Answer 2

So as has already been stated, your problem is that you should always use < size because indexing is 0-based <= size will read off the end of allocated space.
But a couple comments if I may, c++11 introduced a new style of range based for-loops which will save you from having to write the condition and iteration expressions at all:
map<int, string> movSeries = { { 0, "Rock"s }, { 1, "Paper"s }, { 2, "Scissors"s } };
vector<int> fibSeries(10);
auto input = 0;
while(cin >> input) {
for(auto& i : fibSeries) {
i = fib(input++) % 3;
}
cout << "\n\nDebug | ";
copy(cbegin(fibSeries), cend(fibSeries), ostream_iterator<int>(cout, " | "));
cout << "\n\n\n\nDebug | ";
for(const auto i : fibSeries) {
cout << movSeries[i] << " | ";
}
cout << endl << endl;
}