class SparseMatrix extends Matrix {

  public int getNumEntries() {
    int numEntries = 0;
    for (int i = 0; i < this.getRowCount(); i++) {
      numEntries += this.maxIndices[i];
    }
    return numEntries;
  }

  public  SparseMatrix(final int numRows, final int numCols, final int initialCapacityPerRow);

}