Problem with logic when usng if statements - c++

Question

I am writing a small program to accept a name and a score. The program will store data in vectors. Then the program will print the name and score of each entry. Then the program should be able to search for a stored name, and if found display the name and corresponding score, if not found it should display a "not found" message. The program works great, up until the point where a name is entered to be searched, if the name is stored, it will print the name and score correctly. If the name is not found, it will display "not found" correctly as well. The problem is if the name is found, the program will also display the "not found" message as well as the name and score. I am not sure where my logic is flawed.
I have tried using else if, I have tried separate loops, I have tried putting the if statement in the same loop. I have tried using a break statement. Nothing I try will remove the "not found" message when a record is found. Since this is just a program to help me learn, it isn't that big of a deal, however I would like to understand what is going wrong to help me learn more, and to fix this annoying issue.
#include<iostream>
#include<vector>
#include<string>
using namespace std;
inline void keep_window_open() { char ch; cin >> ch; }
vector<string> listOfNames{};
vector<int> listOfScores{};
string name = " ";
int score = 0;
int main()
{
cout << "Please enter a name followed by a score: \n";
cout << "Press enter when finished\n";
cout << "To quit enter NoName 0\n";
while (cin >> name >> score && name != "NoName")
{
for (int i = 0; i < listOfNames.size(); ++i)
{
if (name == listOfNames[i])
{
cout << "error name is a duplicate: \n";
}
}
listOfNames.push_back(name);
listOfScores.push_back(score);
}
cout << "\nlist of names and scores entered\n";
for (int i = 0; i < listOfNames.size(); ++i)
{
cout << listOfNames[i] << ',' << listOfScores[i] << "\n";
}
cout <<"Please enter a name to search for\n";
string searchName = " ";
cin >> searchName;
for (int i = 0; i < listOfNames.size(); ++i)
{
if (searchName == listOfNames[i])
{
cout << listOfNames[i] << ',' << listOfScores[i]<< "\n";
break;
}
}
for (int i = 0; i < listOfNames.size(); ++i)
{
if (searchName != listOfNames[i])
{
cout << "Not found\n";
break;
}
}
keep_window_open();
return 0;
}
If the user enters John 22 and Tim 28, it will print the list, then when a user searched for a name, if the name is not found, it will print "Not found", however if the name is found, it will print the name and score, as it should, but the next line it prints is "Not found". This line should only print if the record is not found.
After doing some more testing I found that if I only enter one value, one name and one score, then do a search, it will not print the "Not found" message after the name and score, it only happens when there are multiple entries. Which confuses me even more. I am not sure why it would work correctly with only one value, and not multiple values.

Answer 1

You made a minor semantic/logical error.
After you have your list with names and scores, you compare all values in the list with the search string. And if you have found it, then you display it. That works fine. No problem.
But in your second loop you have a logical problem. In your list are tons of names that are not equal. And only one is equal. So if you run through you loop, you will ALWAYS find names, that are not equal. And then you will see the output that you do not want to have.
So, your loop is asking: Is any entry in the list "not equal" to the search string. And yes, always any one is.
You need to modify your logic to: Are all values in the list not equal to the search string.
But logically, this is also not necessary. You do not need to run the full loop again. If you have checked for somebody in the list and you found somebody, the he is NOT NOT in the list. And vice versa. So, he either is in the list or not.
You should add a boolean variable to check the state and then add an if/else statement.
I modified a part of code for you:
cout << "Please enter a name to search for\n";
string searchName = " ";
cin >> searchName;
// In this variable, we will store the result of our search, this can be true or false
bool weFoundSomebody = false;
// If we find somebody, then we will remember the index, where we found him.
int indexForFoundGuy = 0;
for (int i = 0; i < listOfNames.size(); ++i)
{
if (searchName == listOfNames[i])
{
weFoundSomebody = true;
indexForFoundGuy = i;
break;
}
}
// Could we find somebody or not. Only one is possible
if (weFoundSomebody)
{
cout << listOfNames[indexForFoundGuy] << ',' << listOfScores[indexForFoundGuy] << "\n";
}
else
{
cout << "Not found\n";
}
keep_window_open();