Ratsun reitit

input/code.cpp: In function 'int main()':
input/code.cpp:100:29: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for (int ti = 0; ti < last_layer.size(); ti++) {
                          ~~~^~~~~~~~~~~~~~~~~~~

/*
possible moves

( 2 ,  1)
( 2 , -1)
(-2 ,  1)
(-2 , -1)
( 1 ,  2)
( 1 , -2)
(-1 ,  2)
(-1 , -2)

possible moves are:

one either of the 1 or 2 and both can be negative or positive
*/

class vec2 {
public:
	int x;
	int y;

	vec2(int x, int y) {
		this->x = x;
		this->y = y;
	}
};

#include <iostream>
#include <vector>

using namespace std;

int size; // size of the board size x size

int** num_moves; // xy
int tiles_left;

#define NUM_POSSIBLE_MOVES 8

vec2 possible_moves[] = {
	vec2( 2 ,  1),
	vec2( 2 , -1),
	vec2(-2 ,  1),
	vec2(-2 , -1),
	vec2( 1 ,  2),
	vec2( 1 , -2),
	vec2(-1 ,  2),
	vec2(-1 , -2)
};

// is tile within board
bool is_move_valid(vec2 coord) {
    int max_coord = size - 1;
    
    return (coord.x <= max_coord && coord.x >= 0) && (coord.y <= max_coord && coord.y >= 0);
}

// check if the tile is already set
bool is_move_set(vec2 coord) {
    return num_moves[coord.x][coord.y] != -1;   
}

// sets a move to the output
void set_move(vec2 coord, int num) {
    tiles_left--;
    num_moves[coord.x][coord.y] = num;
}

int main() {
	cin >> size;
	
	// init number of moves
	num_moves = new int*[size];
	for (int i = 0; i < size; i++) {
		num_moves[i] = new int[size];
	}
	
	// set the values to -1 for keeping track of all unset tiles
	for (int x = 0; x < size; x++) {
	    for (int y = 0; y < size; y++) {
	       num_moves[x][y] = -1;
	    }
	}
	
	tiles_left = size * size;
	
	vec2 start = vec2(0, 0);
	// the last layer is the latest tiles, that the cavalry can be moved in the least number of moves
	vector<vec2> last_layer;
	last_layer.push_back(start);
	
	int moves_made = 0;
	// set the first move (0, 0)
	set_move(start, moves_made++);
	
	// run the loop until every tile has a number of moves
    while (tiles_left > 0) {
        vector<vec2> new_layer;
        for (int ti = 0; ti < last_layer.size(); ti++) {
            for (int mi = 0; mi < NUM_POSSIBLE_MOVES; mi++) {
                // get the tile
                vec2 tile = vec2(last_layer[ti].x + possible_moves[mi].x, last_layer[ti].y + possible_moves[mi].y);
                // if not valid, or is already set, skip
                if (!is_move_valid(tile) || is_move_set(tile)) continue;
                
                
                // if is valid
                // push to the new layer
                new_layer.push_back(tile);
                
                // set move to the output
                set_move(tile, moves_made);
            }
        }
        last_layer = new_layer;
        moves_made++;
    }
    
    // print the output
    
    for (int x = 0; x < size; x++) {
        for (int y = 0; y < size; y++) {
            cout << num_moves[y][x] << " ";
        }
        cout << endl;
    }

    return 0;
}

Test 1

Group: 1, 2, 3

Verdict: ACCEPTED

Test 2

Group: 1, 2, 3

Verdict: ACCEPTED

Test 3

Group: 1, 2, 3

Verdict: ACCEPTED

Test 4

Group: 1, 2, 3

Verdict: ACCEPTED

Test 5

Group: 1, 2, 3

Verdict: ACCEPTED

Test 6

Group: 1, 2, 3

Verdict: ACCEPTED

Test 7

Group: 1, 2, 3

Verdict: ACCEPTED

Test 8

Group: 2, 3

Verdict: ACCEPTED

Test 9

Group: 2, 3

Verdict: ACCEPTED

Test 10

Group: 2, 3

Verdict: ACCEPTED

Test 11

Group: 3

Verdict: ACCEPTED

Test 12

Group: 3

Verdict: ACCEPTED

Test 13

Group: 3

Verdict: ACCEPTED