# UVA 10284 – Chessboard in FEN

This is an easy problem as long as you have done UVA 10196 – Check The Check. I added another “deathByKing” method and just basically used 99% of the old code to solve this problem. The time limit is 3 seconds so a lazy O(N^2) works great.

```import java.awt.Point;
import java.io.PrintWriter;
import java.util.Scanner;
import java.util.StringTokenizer;

/**
*
* @author Sanchit M. Bhatnagar
* @see http://uhunt.felix-halim.net/id/74004
*
*/
public class P10284 {

public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
PrintWriter out = new PrintWriter(System.out);
while (sc.hasNext()) {
char[][] grid = new char[8][8];
StringTokenizer st = new StringTokenizer(sc.next(), "/");
for (int i = 0; i < 8; i++) {
char[] row = st.nextToken().trim().toCharArray();
int idx = 0;
for (Character c : row) {
if (Character.isDigit(c)) {
int tmp = c - '0';
for (int j = idx; j < idx + tmp; j++) {
grid[i][j] = '.';
}
idx += tmp;
} else {
grid[i][idx] = c;
idx++;
}
}
}
int ans = 0;
for (int i = 0; i < 8; i++) {
for (int j = 0; j < 8; j++) {
if (grid[i][j] == '.') {
Point tmp = new Point(i, j);
if (!deathByKing(tmp, grid)) {
int count = 0;
grid[i][j] = 'X';
if (!deathByBishop(tmp, grid) && !deathByKnight(tmp, grid) && !deathByPawn(tmp, grid) && !deathByRook(tmp, grid)) {
count++;
}
grid[i][j] = 'x';
if (!deathByBishop(tmp, grid) && !deathByKnight(tmp, grid) && !deathByPawn(tmp, grid) && !deathByRook(tmp, grid)) {
count++;
}
grid[i][j] = '.';
if (count == 2)
ans++;
}
}
}
}
out.println(ans);
}
out.close();
sc.close();
}

private static boolean deathByKing(Point king, char[][] grid) {
int i = king.x;
int j = king.y;
for (int n = i - 1; n <= i + 1; n++)
for (int m = j - 1; m <= j + 1; m++) {
if (n >= 0 && n < 8 && m >= 0 && m < 8 && (grid[n][m] == 'k' || grid[n][m] == 'K'))
return true;
}
return false;
}

private static boolean deathByBishop(Point king, char[][] grid) {
int i = king.x;
int j = king.y;
char thing = '\u000F';
char thing2 = '\u000F';
if (Character.isLowerCase(grid[i][j])) {
// Black King
thing = 'B';
thing2 = 'Q';
} else {
// White King
thing = 'b';
thing2 = 'q';
}

// NW
int idx = i - 1;
int idx2 = j - 1;
while (idx >= 0 && idx < 8 && idx2 >= 0 && idx2 < 8 && grid[idx][idx2] == '.') {
idx--;
idx2--;
}
if (idx >= 0 && idx < 8 && idx2 >= 0 && idx2 < 8 && (grid[idx][idx2] == thing || grid[idx][idx2] == thing2))
return true;

// NE
idx = i - 1;
idx2 = j + 1;
while (idx >= 0 && idx < 8 && idx2 >= 0 && idx2 < 8 && grid[idx][idx2] == '.') {
idx--;
idx2++;
}
if (idx >= 0 && idx < 8 && idx2 >= 0 && idx2 < 8 && (grid[idx][idx2] == thing || grid[idx][idx2] == thing2))
return true;

// SW
idx = i + 1;
idx2 = j - 1;
while (idx >= 0 && idx < 8 && idx2 >= 0 && idx2 < 8 && grid[idx][idx2] == '.') {
idx++;
idx2--;
}
if (idx >= 0 && idx < 8 && idx2 >= 0 && idx2 < 8 && (grid[idx][idx2] == thing || grid[idx][idx2] == thing2))
return true;

// RIGHT
idx = i + 1;
idx2 = j + 1;
while (idx >= 0 && idx < 8 && idx2 >= 0 && idx2 < 8 && grid[idx][idx2] == '.') {
idx++;
idx2++;
}
if (idx >= 0 && idx < 8 && idx2 >= 0 && idx2 < 8 && (grid[idx][idx2] == thing || grid[idx][idx2] == thing2))
return true;

return false;
}

private static boolean deathByRook(Point king, char[][] grid) {
int i = king.x;
int j = king.y;
char thing = '\u000F';
char thing2 = '\u000F';
if (Character.isLowerCase(grid[i][j])) {
// Black King
thing = 'R';
thing2 = 'Q';
} else {
// White King
thing = 'r';
thing2 = 'q';
}

// UP
int idx = i - 1;
while (idx >= 0 && grid[idx][j] == '.') {
idx--;
}
if (idx >= 0 && idx < 8 && (grid[idx][j] == thing || grid[idx][j] == thing2))
return true;

// DOWN
idx = i + 1;
while (idx < 8 && grid[idx][j] == '.') {
idx++;
}
if (idx >= 0 && idx < 8 && (grid[idx][j] == thing || grid[idx][j] == thing2))
return true;

// LEFT
idx = j - 1;
while (idx >= 0 && grid[i][idx] == '.') {
idx--;
}
if (idx >= 0 && idx < 8 && (grid[i][idx] == thing || grid[i][idx] == thing2))
return true;

// RIGHT
idx = j + 1;
while (idx < 8 && grid[i][idx] == '.') {
idx++;
}
if (idx >= 0 && idx < 8 && (grid[i][idx] == thing || grid[i][idx] == thing2))
return true;

return false;
}

private static boolean deathByKnight(Point king, char[][] grid) {
int i = king.x;
int j = king.y;
char thing = '\u000F';
if (Character.isLowerCase(grid[i][j])) {
// Black King
thing = 'N';
} else {
// White King
thing = 'n';
}
if (i + 2 < 8) {
if (j - 1 >= 0 && grid[i + 2][j - 1] == thing)
return true;
if (j + 1 < 8 && grid[i + 2][j + 1] == thing)
return true;
}
if (i - 2 >= 0) {
if (j - 1 >= 0 && grid[i - 2][j - 1] == thing)
return true;
if (j + 1 < 8 && grid[i - 2][j + 1] == thing)
return true;
}
if (j + 2 < 8) {
if (i - 1 >= 0 && grid[i - 1][j + 2] == thing)
return true;
if (i + 1 < 8 && grid[i + 1][j + 2] == thing)
return true;
}
if (j - 2 >= 0) {
if (i - 1 >= 0 && grid[i - 1][j - 2] == thing)
return true;
if (i + 1 < 8 && grid[i + 1][j - 2] == thing)
return true;
}

return false;
}

private static boolean deathByPawn(Point king, char[][] grid) {
int i = king.x;
int j = king.y;
char thing = '\u000F';
if (Character.isLowerCase(grid[i][j])) {
// Black King
i++;
thing = 'P';
} else {
// White King
i--;
thing = 'p';
}
if (i >= 0 && i < 8) {
if (j - 1 >= 0 && grid[i][j - 1] == thing)
return true;
if (j + 1 < 8 && grid[i][j + 1] == thing)
return true;
}
return false;
}
}
```

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