我的程序返回错误“向量下标超出范围”。

Question

I'm not sure which vector is causing the error or where the issue is coming from. I'm trying to input names and birthdates from a file and set them equal to a part in the vector. The file is:

Mark,12/21/1992
Jay,9/29/1974
Amy Lynn,3/17/2010
Bill,12/18/1985
Julie,7/10/1980
Debbie,5/21/1976
Paul,1/3/2001
Ian,2/29/1980
Josh,10/31/2003
Karen,8/24/2011

I am not even sure if my code accomplishes this because of the error. I tried reading more into stringstream but I did not understand how to correctly implement it. The date class mentioned can be provided if necessary, but it is quite long. Any input on improving the program and why the issue is happening is greatly appreciated. Here is my code:

#include <iostream>
#include <string>
#include <fstream>
#include <vector>
#include "c://cpp/classes/Date.cpp"
using namespace std;

struct person {
    vector<string> name; // One name string vector
    vector<Date> birthdate; // One birthdate vector
    vector<Date> birthday; // birthday vector
};

int main() {
    string input, input2; // Two string inputs
    const int PEOPLE_NUM = 10; // Amount of people

    vector<person> People(PEOPLE_NUM); // Define vector called People with 10 positions
    string test;
    ifstream inputFile("C:/Users/Taaha/Documents/CMSC226/Project 3/Names.txt", ios::in);
    for (int i = 0; i < PEOPLE_NUM; i++) {
        getline(inputFile, input, ','); // input the line, stop when a comma
        People[i].name[i] = input; // Add input into the vector 
        getline(inputFile, input2, ',');
        People[i].birthdate[i] = input2;
        cout << i;
    }
    inputFile.close(); // close file

    Date birthday;
    for (int i = 0; i < PEOPLE_NUM; i++) {
        Date birthday(People[i].birthday[i].getDay(), People[i].birthday[i].getMonth(), Date().getYear());
        People[i].birthday[i] = birthday;
    } // Not finished yet, but turns birthdate into birthday
    return 0;
}

Thanks again :]

Answer 1

When People[i].name[i] = input; in the for loop, People[i].name is still a empty vector, call operator[] on it will be UB. You might resize them in advance, or use push_back .

for (int i = 0; i < PEOPLE_NUM; i++) {
    getline(inputFile, input, ',');
    People[i].name[i] = input;        // People[i].name is still empty here 
    getline(inputFile, input2, ',');
    People[i].birthdate[i] = input2;  // People[i].birthdate is still empty here
    cout << i;
}

You might use push_back , such as,

for (int i = 0; i < PEOPLE_NUM; i++) {
    getline(inputFile, input, ',');
    People[i].name.push_back(input); 
    //            ~~~~~~~~~~
    getline(inputFile, input2, ',');
    People[i].birthdate.push_back(input2);
    //                 ~~~~~~~~~~
    cout << i;
}

And it's same for another for loop.

for (int i = 0; i < PEOPLE_NUM; i++) {
    Date birthday(People[i].birthdate[i].getDay(), People[i].birthdate[i].getMonth(), Date().getYear());  // typo of birthdate?
    //                      ~~~~~~~~~                        ~~~~~~~~~
    People[i].birthday.push_back(birthday);
    //                 ~~~~~~~~~~
} // Not finished yet, but turns birthdate into birthday