Skip to content

Instantly share code, notes, and snippets.

@sachinsmc

sachinsmc/Hit.java

Created Aug 12, 2017
Embed
What would you like to do?
import java.io.BufferedReader;
import java.io.InputStreamReader;
class Hit {
static int arr[][], N;
public static void main(String args[]) throws Exception {
BufferedReader ob = new BufferedReader(new InputStreamReader(System.in));
N = Integer.parseInt(ob.readLine());
arr = new int[N][N];
int arrCopy[][] = new int[N][N];
String inps[];
for (int i = 0; i < N; i++) {
inps = ob.readLine().split(" ");
for (int j = 0; j < N; j++) {
arr[i][j] = Integer.parseInt(inps[j]);
}
}
//copying
for (int i = 0; i < N; i++) {
System.arraycopy(arr[i], 0, arrCopy[i], 0, N);
}
//checking first row
boolean case1, case2;
case1 = case2 = false;
for (int i = 0; i < N; i++) {
if (arr[0][i] == 1) {
if (rowPath(0, i)) {
case1 = true;
break;
}
}
}
//pasting
for (int i = 0; i < N; i++) {
System.arraycopy(arrCopy[i], 0, arr[i], 0, N);
}
//checking first column
for (int i = 0; i < N; i++) {
if (arr[i][0] == 2) {
if (columnPath(i, 0)) {
case2 = true;
break;
}
}
}
if (case1 && case2) {
System.out.println("AMBIGUOUS");
} else if (case1) {
System.out.println("1");
} else if (case2) {
System.out.println("2");
} else {
System.out.println("0");
}
}
static boolean rowPath(int r, int c) {
if (arr[r][c] == 0 || arr[r][c] == 2) {
return false;
}
if (r == N - 1) {
return true;
}
boolean r1, r2, r3;
arr[r][c]=0;
r1 = r3 = false;
if (c > 0) {
r1 = rowPath(r + 1, c - 1);
if (!r1) {
arr[r + 1][c - 1] = 0;
}
}
r2 = rowPath(r + 1, c);
if (!r2) {
arr[r + 1][c] = 0;
}
if (c < N - 1) {
r3 = rowPath(r + 1, c + 1);
if (!r3) {
arr[r + 1][c + 1] = 0;
}
}
return r1 || r2 || r3;
}
static boolean columnPath(int r, int c) {
if (arr[r][c] == 0 || arr[r][c] == 1) {
return false;
}
if (c == N - 1) {
return true;
}
if (arr[r][c] == 2) {
boolean r1, r2, r3;
arr[r][c]=0;
r1 = r3 = false;
if (r > 0) {
r1 = columnPath(r - 1, c + 1);
if (!r1) {
arr[r - 1][c + 1] = 0;
}
}
r2 = columnPath(r, c + 1);
if (!r2) {
arr[r][c + 1] = 0;
}
if (r < N - 1) {
r3 = columnPath(r + 1, c + 1);
if (!r3) {
arr[r + 1][c + 1] = 0;
}
}
return r1 || r2 || r3;
}
return false;
}
}
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment