eminv1.0

#include <iostream>

using namespace std;

const int MaxN = 100;

struct CarT{
    string date;
    int amount;
    int quantities;
};

int main()
{
    //declaration
    CarT car[MaxN];
    int N;
    bool exist;
    string when;
    int sum;
    int cnt;


    //input
    bool error1 = false;
    do{
        cout<<"How many items are there?: ";
        cin>>N;
        error1 = ((N<1) || (N>MaxN));
        if(error1){
            cout<<"Not good. Please gove another value. "<<endl;
            }

    }while(error1);

    for(int i = 0; i<N; i++){
        cout<<" What is the "<<i+1<<" item's date?: ";
        cin>>car[i].date;
        bool error2 = false;
        do{
        cout<<" What is the "<<i+1<<" item's amount?: ";
        cin>>car[i].amount;
        error2 = (car[i].amount < 0);
        if(error2){
            cout<<"Not good. Please give another value. "<<endl;
        }
        }while(error2);
        bool error3 = false;
        do{
        cout<<" What is the "<<i+1<<" item's quantities?: ";
        cin>>car[i].quantities;
        error3 = (car[i].quantities < 0);
        if(error3){
            cout<<"Not good. Please give another value. "<<endl;
        }
        }while(error3);


    }

    cout<<"\n";
    //algorithm

    int i = 0;
    while((i <= N) && (car[i].amount != 20000)){
        i+=1;
    }
    exist = (i<=N);

    sum = 0;
    for(int i = 0; i<N; i++){
        sum = sum + car[i].amount;
    }


    //output
    if(exist){
        when = car[i].date;
        cout<<"We payed exactly 20000 on the "<<when<<" date."<<endl;
    }else{
        when = "never";
        cout<<when<<endl;
    }

    cout<<"The amount that we spent on gasoline is: "<<sum<<endl;

    return 0;
}