package Question17_5;
import java.util.Random;
public class Question {
public static class Result {
public int hits;
public int pseudoHits;
public Result(int h, int p) {
hits = h;
pseudoHits = p;
}
public Result() {
}
public String toString() {
return "(" + hits + ", " + pseudoHits + ")";
}
};
public static int code(char c) {
switch (c) {
case 'B':
return 0;
case 'G':
return 1;
case 'R':
return 2;
case 'Y':
return 3;
default:
return -1;
}
}
public static int MAX_COLORS = 4;
public static Result estimate(String guess, String solution) {
if (guess.length() != solution.length()) return null;
Result res = new Result();
int[] frequencies = new int[MAX_COLORS];
/* Compute hits and built frequency table */
for (int i = 0; i < guess.length(); i++) {
if (guess.charAt(i) == solution.charAt(i)) {
res.hits++;
} else {
/* Only increment the frequency table (which will be used for pseudo-hits) if
* it's not a hit. If it's a hit, the slot has already been "used." */
int code = code(solution.charAt(i));
if (code >= 0) {
frequencies[code]++;
}
}
}
/* Compute pseudo-hits */
for (int i = 0; i < guess.length(); i++) {
int code = code(guess.charAt(i));
if (code >= 0 && frequencies[code] > 0 && guess.charAt(i) != solution.charAt(i)) {
res.pseudoHits++;
frequencies[code]--;
}
}
return res;
}
/************************** TEST CODE **********************************/
public static char letterFromCode(int k) {
switch (k) {
case 0:
return 'B';
case 1:
return 'G';
case 2:
return 'R';
case 3:
return 'Y';
default:
return '0';
}
}
public static Result estimateBad(String g, String s) {
char[] guess = g.toCharArray();
char[] solution = s.toCharArray();
int hits = 0;
for (int i = 0; i < guess.length; i++) {
if (guess[i] == solution[i]) {
hits++;
solution[i] = '0';
guess[i] = '0';
}
}
int pseudohits = 0;
for (int i = 0; i < guess.length; i++) {
if (guess[i] != '0') {
for (int j = 0; j < solution.length; j++) {
if (solution[j] != '0') {
if (solution[j] == guess[i]) {
pseudohits++;
solution[j] = '0';
break;
}
}
}
}
}
return new Result(hits, pseudohits);
}
public static String randomString() {
int length = 4;
char[] str = new char[length];
Random generator = new Random();
for (int i = 0; i < length; i++) {
int v = generator.nextInt(4);
char c = letterFromCode(v);
str[i] = c;
}
return String.valueOf(str);
}
public static boolean test(String guess, String solution) {
Result res1 = estimate(guess, solution);
Result res2 = estimateBad(guess, solution);
if (res1.hits == res2.hits && res1.pseudoHits == res2.pseudoHits) {
return true;
} else {
System.out.println("FAIL: (" + guess + ", " + solution + "): " + res1.toString() + " | " + res2.toString());
return false;
}
}
public static boolean testRandom() {
String guess = randomString();
String solution = randomString();
return test(guess, solution);
}
public static boolean test(int count) {
for (int i = 0; i < count; i++) {
if (!testRandom()) {
return true;
}
}
return false;
}
/********************** END TEST CODE ************************/
public static void main(String[] args) {
test(1000);
}
}