01204212/spreadsheet
ไปยังการนำทาง
ไปยังการค้นหา
- This is part of 01204212
Examples
> A10=5 > B10=20 > A12=30 > A10 5 > B12345=12345 > B12345 12345 > quit
Code
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.HashMap;
import java.util.Map;
public class Main {
Map<Integer,Integer> table;
public static void main(String[] args) throws IOException {
Main m = new Main();
m.process();
}
Main() {
table = new HashMap<Integer, Integer>();
}
private void process() throws IOException {
BufferedReader reader = new BufferedReader(
new InputStreamReader(System.in) );
System.out.println("Hello!");
while(true) {
System.out.print("> ");
String cmd = reader.readLine();
if(cmd.equals("quit")) {
return;
}
if(cmd.contains("=")) {
String[] items = cmd.split("=");
int cellNum = getCellNumber(items[0]);
int val = Integer.parseInt(items[1]);
table.put(cellNum, val);
} else {
int cellNum = getCellNumber(cmd);
Integer val = table.get(cellNum);
if(val == null) {
val = 0;
}
System.out.println(val);
}
}
}
private int getCellNumber(String location) {
location = location.toUpperCase();
try {
int colNum = 0;
int i = 0;
while((location.charAt(i) >= 'A') &&
(location.charAt(i) <= 'Z')) {
colNum = colNum * 26 + (location.charAt(i) - 'A');
i++;
}
String rowStr = location.substring(i);
int rowNum = Integer.parseInt(rowStr);
return colNum * 1000000 + rowNum;
} catch(Exception e) {
return -1;
}
}
}
Hash table (linear probing)
public class HashTable {
static final int M = 1000;
static final int P = 997;
static final int EMPTY_KEY = -1;
int [] values;
int [] keys;
public HashTable() {
values = new int[M];
keys = new int[M];
for(int i=0; i<M; i++) {
keys[i] = EMPTY_KEY;
}
}
int hash(int key) {
return key % P; // VERY BAD HASH FUNCTION. YOU HAVE TO CHANGE THIS
}
void put(int k, int v) {
int idx = hash(k);
//System.out.println("H = " + idx);
while((keys[idx] != EMPTY_KEY) && (keys[idx] != k)) {
idx++;
if(idx == M) {
idx = 0;
}
//System.out.println("Not empty move to " + idx);
}
keys[idx] = k;
values[idx] = v;
}
int get(int k) {
int idx = hash(k);
//System.out.println("H = " + idx);
while((keys[idx] != k) && (keys[idx] != EMPTY_KEY)) {
idx++;
if(idx == M) {
idx = 0;
}
//System.out.println("Not the key, move to " + idx);
}
if(keys[idx] == k) {
return values[idx];
} else {
throw new RuntimeException("Sorry");
}
}
}