SparseArrayRunner

import java.util.ArrayList;
import java.util.List;

class SparseArrayEntry {
    private int row;
    private int col;
    private int value;

    public SparseArrayEntry(int r, int c, int v) {
        row = r;
        col = c;
        value = v;
    }

    public int getRow() {
        return row;
    }

    public int getCol() {
        return col;
    }

    public int getValue() {
        return value;
    }

    public String toString() {
        return "\nrow :: " + getRow() +
                "\ncol :: " + getCol() +
                "\nvalue :: " + getValue() + "\n";
    }
}

class SparseArray {
    private int numRows;
    private int numCols;

    private List<SparseArrayEntry> entries;

    public SparseArray() {
        entries = new ArrayList<SparseArrayEntry>();

        entries.add(new SparseArrayEntry(1, 4, 4));
        entries.add(new SparseArrayEntry(2, 0, 1));
        entries.add(new SparseArrayEntry(3, 1, -9));
        entries.add(new SparseArrayEntry(1, 1, 5));
        entries.add(new SparseArrayEntry(3, 2, 18));
    }

    public int getNumRows() {
        return numRows;
    }

    public int getNumCols() {
        return numCols;
    }

    public int getValueAt(int row, int col) {
        for (SparseArrayEntry entry : entries) {
            if (entry.getRow() == row && entry.getCol() == col)
                return entry.getValue();
        }
        return 0;
    }

    public void removeColumn(int col) {
        for (int i = 0; i < entries.size(); i++) {
            if (entries.get(i).getCol() == col) {
                entries.remove(i);
                i--;
                continue;
            }
            if (entries.get(i).getCol() > col)
                entries.set(i, new SparseArrayEntry(entries.get(i).getRow(), entries.get(i).getCol() - 1, entries.get(i).getValue()));
        }
    }

    public String toString() {
        return entries.toString().replaceAll("\\[", "").replaceAll("]", "").replaceAll(",", "");
    }
}

public class SparseArrayRunner {
    public static void main(String[] args) {
        SparseArray test = new SparseArray();
        System.out.println("entry at 3,1 is " + test.getValueAt(3, 1) + "\n");
        System.out.println("entry at 3,2 is " + test.getValueAt(3, 2) + "\n");
        test.removeColumn(1);
        System.out.println(test);
        System.out.println("entry at 3,1 is " + test.getValueAt(3, 1) + "\n");
        System.out.println("entry at 3,2 is " + test.getValueAt(3, 2) + "\n");
    }
}