Time limit exceeded using Scanner - Java

Question

I'm testing this code in Java with a problem from a programming Judge and I get a "time limit" error. I guess the scanner.hasNextDouble() thingy is not working somehow.

It works with the public inputs shown in the link but it throws this time limit error with the privates.

Any idea to solve this issue?

import java.util.Scanner;
import java.text.NumberFormat;
import java.util.Locale;

class Main /*AvalPoli2*/ {
    public static void main(String[] args) {
        NumberFormat nf = NumberFormat.getNumberInstance(Locale.US); // dot sep.
        nf.setGroupingUsed(false); // don't group in groups of 3 
        nf.setMaximumFractionDigits(4); 
        nf.setMinimumFractionDigits(4);
        Scanner scanner = new Scanner(System.in);
        scanner.useLocale(Locale.US); // read doubles with dot separator
        double sum = 0.0000;
        double x = 0;
        if (scanner.hasNextDouble()) x = scanner.nextDouble();
        while (scanner.hasNextDouble()) {
            sum *= x;
            sum += scanner.nextDouble();
        }
        System.out.println(nf.format(sum));
    }
}

Thank you very much! ^_^

No exception or error, looks like the loop never ends or the program waits for input forever. — FullAdder, Jun 25 '12 at 12:24
But it works with the inputs shown in this link, and matches the outputs: https://www.jutge.org/problems/P72986_en (ignore security warning, university SSL is not verified) The problem is with the inputs that are not shown, they are more challenging. — FullAdder, Jun 25 '12 at 12:31

score 1 · Answer 1 · answered Jan 22 '14 at 19:05

1

You have to Wrap your System.in, like

BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
in = new Scanner(br);

instead,

in = new Scanner(System.in);

answered Jan 22 '14 at 19:05

Sazzad Hissain Khan

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score 0 · Answer 2 · answered Feb 25 '23 at 04:54

You can create a Reader class by yourself, here is my Reader class code.

/** Reader Class */
static class Reader {
    BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
    StringTokenizer tokenizer = new StringTokenizer("");

    /** Get next line text */
    String next() throws IOException {
        while (!tokenizer.hasMoreTokens()) {
            tokenizer = new StringTokenizer(reader.readLine());
        }
        return tokenizer.nextToken();
    }

    int nextInt() throws IOException {
        return Integer.parseInt(next());
    }

    double nextDouble() throws IOException {
        return Double.parseDouble(next());
    }
}

To use this class, you need to create an object(assume it named reader). To get a int number, you should reader.nextInt(). To get a Double number, you should reader.nextDouble.

Time limit exceeded using Scanner - Java

2 Answers2