C++ String Array search outputs for every item - c++

Question

I know it's somewhat confusing this title of question but I really need help.
I need to find a string in array with many strings. If the string is not found then the appropriate message is showed. However when I use for loop, it then shows this message for every string in array which is not found although it also shows found string... I hope you understand what I mean and sorry if i'm not making sense. here's my code:
void Store::search() {
string name;
cout << "Enter name of product you're searching: " << endl;
getline(cin, name);
for (int i = 0; i < quantity; i++) {
if (name.compare(database[i].name) == 0){
cout << "-------------<Product found!>-------------" << endl;
cout << "name: " << database[i].name << endl;
cout << "supplier: " << database[i].supplier << endl;
cout << "available quantity: " << database[i].quantity<< endl;
cout << "price per unit: " << database[i].price<< endl;
cout << "------------------------------------------" << endl;
}
else
{
cout << "Product doesn't exist in database!" << endl;
}
}
}
The code works for searching but how do I stop the output "Product doesn't exist in database!" for every item in array that is not found(even when searched item is found)?
Thank You in advance

Answer 1

You can use statement flag:
void Store::search()
{
string name;
bool found = false
cout << "Enter name of product you're searching: " << endl;
getline(cin, name);
for (int i = 0; i < quantity; i++)
{
if (name.compare(database[i].name) == 0){
cout << "-------------<Product found!>-------------" << endl;
cout << "name: " << database[i].name << endl;
cout << "supplier: " << database[i].supplier << endl;
cout << "available quantity: " << database[i].quantity<< endl;
cout << "price per unit: " << database[i].price<< endl;
cout << "------------------------------------------" << endl;
found = true;
break;
}
if (!found)
cout << "Product doesn't exist in database!" << endl;
}

Answer 2

You can also use std::find_if, which will make your code look something like:
auto it = std::find_if(databases.begin(), databases.end(), [&name](const auto &database) {return name.compare(database.name) == 0; });
if (it != databases.end())
{
cout << it->name << endl;
cout << "found" << endl;
}
else
{
cout << "not found" << endl;
}
Generally speaking, C++ offers many such features that more often than not will make your code shorter, improve readability and guarantee functionality

Answer 3

You can:
1. keep a bool variable to be set to true if the item is found in the for loop
2. add a break to immediately exit for loop when item is found
3. remove the else part, because it will print out "Product doesn't exist in database!" for each loop cycle if the item does not match
4. after the for loop, check if found is false to check if item does not exist in collection
bool found = false;
for (int i = 0; i < quantity; i++)
{
if (name.compare(database[i].name) == 0)
{
cout << "-------------<Product found!>-------------" << endl;
cout << "name: " << database[i].name << endl;
cout << "supplier: " << database[i].supplier << endl;
cout << "available quantity: " << database[i].quantity<< endl;
cout << "price per unit: " << database[i].price<< endl;
cout << "------------------------------------------" << endl;
found = true; // set "found" to true
break; // add a break to immediately exit for loop when item is found
}
}
if (!found)
{
cout << "Product doesn't exist in database!" << endl;
}

Answer 4

I assume you want to search a product in the database and print its details if found. Otherwise you want to notify user that the product was not found. If I understood you correctly, then you need to move the else statement out of 'for' loop, e.g.:
void Store::search() {
string name;
cout << "Enter name of product you're searching: " << endl;
getline(cin, name);
bool found = false;
for (int i = 0; i < quantity; i++) {
if (name.compare(database[i].name) == 0){
cout << "-------------<Product found!>-------------" << endl;
cout << "name: " << database[i].name << endl;
cout << "supplier: " << database[i].supplier << endl;
cout << "available quantity: " << database[i].quantity<< endl;
cout << "price per unit: " << database[i].price<< endl;
cout << "------------------------------------------" << endl;
found = true;
break;
}
}
if (!found)
{
cout << "Product doesn't exist in database!" << endl;
}
}
If your database may contain more products with the same name, remove 'break;' statement.

Answer 5

A more "modern C++" approach is to leverage the C++ algorithms (such as std::find_if), lambdas and maybe the auto specifier.
As example (assuming database is a std::vector or some kind of STL container):
auto it = std::find_if(database.begin(), database.end(), [&name](const auto& item) { return name.compare(item.name) == 0; });
if (it != database.end())
{
cout << it->name << endl;
cout << "found" << endl;
}
else
{
cout << "not found" << endl;
}