UVA 10114 - Loansome Car Buyer

#include <iostream>
#include <vector>
using namespace std;

int main() {
    int loanDur, nRec;
    double downPayment, loan, decP[101];

    while (true) {
        cin >> loanDur >> downPayment >> loan >> nRec;
        if (loanDur < 0)
            break;

        int m;
        double p;
        while (nRec--) {
            cin >> m >> p;
            for (int i = m; i < 101; i++)
                decP[i] = p;
        }

        int now = 0;
        double monthlyPayment = loan / loanDur;
        double curVal = (loan + downPayment) * (1 - decP[0]);
        double curLoan = loan;
        while (curVal < curLoan) {
            now++;
            curLoan -= monthlyPayment;
            curVal = curVal * (1-decP[now]);
        }

        cout << now << " month";
        if (now != 1)
            cout << "s";
        cout << endl;
    }

    return 0;
}