#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <stdbool.h>
/**
* Auto-generated code below aims at helping you parse
* the standard input according to the problem statement.
**/
////////////////////////////////////// TO DO
///////////////////////////////////// LOOPtester: int tile[L][C+1][4]; // tile[a][b] = {breaker?,
inverted?, direction, number of X};
////////////////////////////////////
run to checkloop count turns then print 1 by 1 for a lighter usage
of memory
// void _checkloop(tilerec, grid)
bool _isnextvalid(char next, bool breaker){
if((next == 'X' && breaker == false) || next == '#') return false;
else return true;
}
bool _loopscan(int tile[4], bool breaker, bool inverted, int direction, int Xctr){
if(tile[0] == (int)(breaker) && tile[1] == (int)(inverted) && tile[2] == direction &&
tile[3] == Xctr){
return true;
}else return false;
}
int main(int argc, char * argv[]){
int L; // h
int C; // w
scanf("%d%d", &L, &C); fgetc(stdin);
int turns = 0;
int xy[2], nextxy[2]; // holders, xy: current position. xy[0] = abs, xy[1] = ord.
char grid[L][C+1]; // recording gamegrid
int Xctr = 0;
int Tloc[2][2], tctr = 0; // teleporters locations, numbers of teleporters
int trail[L][C+1][3]; // keeping track of each visited tile
for(int i = 0; i < L; i++){
for(int j = 0; j < C; j++){
for(int jj = 0; jj < 3; jj++){
trail[i][j][jj] = -1;
}
}
}
//////////////////////////// Recording
Inputs/Grid
for (int i = 0; i < L; i++) {
scanf("%[^\n]", grid[i]); fgetc(stdin);
//tester
fprintf(stderr, "%s\n", grid[i]);
//OK
for(int ii = 0; ii < C; ii++){
if(grid[i][ii] == '@'){
xy[0] = ii; xy[1] = i; // scanning starting point
//tester
//fprintf(stderr, "\n@ (%d , %d)\n", ii, i);
//OK
}else if(grid[i][ii] == 'T'){ //scanning teleporter
Tloc[tctr][0] = ii; Tloc[tctr][1] = i; tctr++;
//tester
//fprintf(stderr, "\nt_%d (%d , %d)\n", tctr, ii, i);
//OK
}else if(grid[i][ii] == 'X'){ // counting Obstacles
Xctr++;
}
}
}
char spec[] = "SENW";
char moveset[4][6] = {"SOUTH", "EAST", "NORTH", "WEST"};
int move[4][3] = {{0, 1, 0}, {1, 0, 1}, {0, -1, 2}, {-1, 0, 3}}; // vectorial vect[k][0] = abs,
vect[k][1] = ord, vect[k][2] = rank in moveset.
bool inverted = false, breaker = false, blocked = false;
int direction = 0;
trail[xy[1]][xy[0]][0] = breaker;
trail[xy[1]][xy[0]][0] = inverted;
trail[xy[1]][xy[0]][0] = direction;
trail[xy[1]][xy[0]][0] = Xctr;
//getmov
while(grid[xy[1]][xy[0]] != '$'){
if(_loopscan(trail[xy[1]][xy[0]], breaker, inverted, direction, Xctr)){
printf("LOOP\n");
return 0;
}
//fprintf(stderr, "\nxy0: %d, xy1: %d\n", xy[0], xy[1]);
if(grid[xy[1]][xy[0]] == 'I'){
if(inverted == true) inverted = false;
else inverted = true;
}
if(grid[xy[1]][xy[0]] == 'B'){
if(breaker == true) breaker = false;
else breaker = true;
//fprintf(stderr, "\nturn: %d, break: %d\n", turns, breaker);
}
for(int i = 0; i < 4; i++){
if(grid[xy[1]][xy[0]] == spec[i]){
direction = i; break;
}
}
//get nextxy
nextxy[0] = xy[0] + move[direction][0];
nextxy[1] = xy[1] + move[direction][1];
if(grid[nextxy[1]][nextxy[0]] == 'T'){
if(nextxy[0] == Tloc[0][0] && nextxy[1] == Tloc[0][1]){
nextxy[0] = Tloc[1][0];
nextxy[1] = Tloc[1][1];
}else{
nextxy[0] = Tloc[0][0];
nextxy[1] = Tloc[0][1];
}
}else if(grid[nextxy[1]][nextxy[0]] == 'X' && breaker == true){
grid[nextxy[1]][nextxy[0]] = ' ';
Xctr--;
}
//if blocked, unblocked. if impossible return loop;
if(!_isnextvalid(grid[nextxy[1]][nextxy[0]], breaker)){
blocked = true;
while(blocked == true){
if(inverted == true){
for(int i = 3; i > -1; i--){
direction = i;
nextxy[0] = xy[0] + move[i][0];
nextxy[1] = xy[1] + move[i][1];
if(_isnextvalid(grid[nextxy[1]][nextxy[0]], breaker)){
blocked = false;
break;
}
}
if(blocked != false){
printf("LOOP\n");
return 0;
}
}else{
for(int i = 0; i < 4; i++){
direction = i;
nextxy[0] = xy[0] + move[i][0];
nextxy[1] = xy[1] + move[i][1];
if(_isnextvalid(grid[nextxy[1]][nextxy[0]], breaker)){
blocked = false;
break;
}
}
if(blocked != false){
printf("LOOP\n");
return 0;
}
}
}
}
//update data
xy[0] = nextxy[0];
xy[1] = nextxy[1];
turns++;
// trail[a][b] = {breaker?, inverted?,
direction, number of X};
trail[xy[1]][xy[0]][0] = breaker;
trail[xy[1]][xy[0]][0] = inverted;
trail[xy[1]][xy[0]][0] = direction;
trail[xy[1]][xy[0]][0] = Xctr;
printf("%s\n", moveset[direction]);
}
/* if(grid[xy[1]][xy[0]] == '$'){
for(int i = 0; i < turns; i++){ ///////////////// replace 1 with 0 when loop problem solved
OK BRO?
//fprintf(stderr, "%s\n", moveset[HSHdirection[i]]);
printf("%s\n", ;
}
}
*/
return 0;
}
/*
//tester printer ///////////////////////////////////
switch(direction){
case 0:
pgrid[xy[1]][xy[0]] = 'v';
break;
case 1:
pgrid[xy[1]][xy[0]] = '>';
break;
case 2:
pgrid[xy[1]][xy[0]] = '^';
break;
case 3:
pgrid[xy[1]][xy[0]] = '<';
break;
}
fprintf(stderr, "\n\n");
for (int i = 0; i < L; i++) {
//tester
fprintf(stderr, "%s\n", pgrid[i]);
strcpy(pgrid[i], grid[i]);
//OK
}
fprintf(stderr, "\n%s\t turns: %d\thsh: %d\n", moveset[direction], turns,
HSHdirection[turns]);
//////////////////////////////////////////
*/