bank.cc

#include <iostream>
#include <cstdlib>
#include <fstream>

using namespace std;

int nextAvailable(unsigned int C, int *chashier)
{

    int avail = 0;
    int min = chashier[0];

    for (int i=1; i<C; ++i) {
        if (chashier[i]<min) {
            min = chashier[i];
            avail = i;
        }
    }

    return avail;
}

int main(int argc, const char *argv[])
{
    string inFileName;

    switch (argc) {
        case 2:
            inFileName = argv[1];
            break;
        default:
            cout << "Usage: " << argv[0] << " inputFile" << endl;
            exit(0);
            break;
    }

    fstream inFile(inFileName.c_str(),fstream::in);
    if (!inFile.is_open()) {
        cout << "File " << inFileName << " is not open!" << endl;
        exit(1);
    }


    unsigned int C = 0; // number of cashiers
    unsigned int N = 0; // number of clients
    int maxWaiting = 20;
    int clientsOverTime = 0;

    if(!(inFile >> C >> N)){
        cout << "Error, can't read C and N!" << endl;
        exit(1);
    }


    int *cashier = new int [C]; // time when the cashier is free
    for (int i=0; i<C; ++i)
        cashier[i] = 0;

    for (unsigned int iN = 0; iN < N; ++iN) {
        int T = 0; // time that the client arrived on the line
        int D = 0; // attendance time
        if(!(inFile >> T >> D)){
            cout << "Error, can't read T or D!" << endl;
            exit(1);
        }

        int avail = nextAvailable(C, cashier);

        int waitTime = cashier[avail] - T;

        if (waitTime > maxWaiting)
            ++clientsOverTime;

        cashier[avail] = (waitTime > 0) ? cashier[avail] : T;
        cashier[avail] += D;


    }

    cout << clientsOverTime << endl;
    
    inFile.close();
    
    delete [] cashier;
    return 0;  
}