如何列出向量中存储的结构迭代次数

我是 c++ 的新手(以及一般的编码(，最近一直在使用向量中保存的结构，在这种情况下：

struct Contact{
    string name;
    string address;
    string phone;
    string email;};
vector<Contact> contacts;

因此，我的一个函数涉及搜索每个联系人，以查找名称中存储的字符串与搜索输入匹配的联系人。为此，我做了一个 for 循环：

for(int i = 0; i < contacts.size(); i++){
    if(contacts[i].name == searchInput){
        cout << contacts[i].address << "nr" << contacts[i].phone << "nr" << contacts[i].email;

但是由于某种原因，这只能找到正确的联系人，如果它是存储在以下位置的名称：

contacts[0].name

没有其他人。因此，在试图找出问题所在时，我决定这样做

cout << contacts.size();

我认为应该输出 3，因为我只存储了三个联系人。然而，由于某种原因，它输出 7。无论如何，我是否可以准确列出存储在联系人向量中的联系人迭代次数以使我的 for 循环正常工作？

编辑我的完整代码：

#include <vector>
#include <iostream>
#include <fstream>
using namespace std;
struct Contact
{
    string name;
    string address;
    string phone;
    string email;
};
bool go;
bool a = false;
char command;
string endL = "nr";
string tab = "t";
string line;
int i;
int counter = 0;
int contactCounter = 0;
vector<Contact> contacts;
void add(){
    contacts.push_back(Contact());
    int newcontact = contacts.size() - 1;
    string input;
    cout << "Enter the name: " << endL;
    cin >> input;
    contacts[newcontact].name = input;
    cout << "Enter the address: " << endL;
    cin >> input;
    contacts[newcontact].address = input;
    cout << "Enter the phone number: " << endL;
    cin >> input;
    contacts[newcontact].phone = input;
    cout << "Enter the email address: " << endL;
    cin >> input;
    contacts[newcontact].email = input;
}

void search(string name){
    for(int i = 0; i < contacts.size(); i++){
        if(contacts[i].name == name){
            cout << "Name: " << contacts[i].name << endL << "Address: " << contacts[i].address << endL << "Phone Number: " << contacts[i].phone << endL << "Email: " << contacts[i].email << endL << endL;
            a = true;
        }
    }
    if(a == false){
        cout << "There is no contact under that name." << endL;
    }
}
int main() {
    ifstream phonebook;
    phonebook.open("phonebook.txt");
if(phonebook.is_open()){
    while(getline(phonebook,line)){
        if(line.empty() == false){
            if(counter % 4 == 0){
                contacts.push_back(Contact());
                contacts[contactCounter].name = line;
            }else if(counter % 4 == 1){
                contacts[contactCounter].address = line;
            }else if(counter % 4 == 2){
                contacts[contactCounter].phone = line;
            }else if(counter % 4 == 3){
                contacts[contactCounter].email = line;
                contactCounter++;
            }
            counter++;
        }
    }
    }else{cout << "an error has occurred while opening the phonebook";}
   phonebook.close();
   cout << contacts.size() << endL;
    cout << "Enter a command." << endL << tab << "To add a contact, enter '+'" << endL << tab << "To search for a contact, enter 's'" << endL << tab << "To delete a contact, enter '-'" << endL << tab << "To quit the program, enter 'q'" << endL;
    cin >> command;
    while(command != 'q'){
        if(command == '+'){
            add();
            command = '/';
        }
        else if(command == 's'){
            string searched;
            cout << "Please enter who you would like to search for: ";
            cin >> searched;
            search(searched);
            command = '/';
        }
        else if(command == '-'){
            cout << "Not done." << endL;
            command = '/';
        }
        else if(command == '/'){
            cout << "Enter a command." << endL << tab << "To add a contact, enter '+'" << endL << tab << "To search for a contact, enter 's'" << endL << tab << "To delete a contact, enter '-'" << endL << tab << "To quit the program, enter 'q'" << endL;
            cin >> command;
        }
        else{
            cout << "That command is invalid." << endL;
            cout << "Enter a command." << endL << tab << "To add a contact, enter '+'" << endL << tab << "To search for a contact, enter 's'" << endL << tab << "To delete a contact, enter '-'" << endL << tab << "To quit the program, enter 'q'" << endL;
            cin >> command;
        }

    }
    ofstream newbook;
   newbook.open("phonebook.txt");
   if(newbook.is_open()){
        for(int i=0; i < contacts.size(); i++){
            newbook << contacts[i].name << endl;
            newbook << contacts[i].address << endl;
            newbook << contacts[i].phone << endl;
            newbook << contacts[i].email << endl;
            newbook << endL;
        }
   }else{cout << "there was an issue saving your contacts" << endL;}
    newbook.close();
return 0;
}