A function about checking whether the game is over in 2048 game - c++

Question

I took some days to code 2048 game. And now I made most of the functions but one, testing whether the game is over. To code this game, my idea is to merge the same numbers first with the function up(down, left or right)_merge and make all the numbers go to the arrow direction that user presses with the function all_go_up(down, left or right). And then add a new number with the add_new_number function.
Here are some piece of those code I mentioned above:
void up_merge()
{
for(int i = 1; i < 4; i++) {
for(int j = 0; j < 4; j++) {
if(grid[i][j] > 0 && grid[i - 1][j] == grid[i][j]) {
while(grid[i - 1][j] == grid[i][j]) {
grid[i - 1][j] *= 2;
grid[i][j] = 0;
}
}
else if(grid[i][j] > 0 && grid[i - 1][j] == 0 && grid[i - 2][j] == grid[i][j]) {
while(grid[i - 2][j] == grid[i][j]) {
grid[i - 2][j] *= 2;
grid[i][j] = 0;
}
}
else if(grid[i][j] > 0 && grid[i - 1][j] == 0 && grid[i - 2][j] == 0 && grid[i - 3][j] == grid[i][j]) {
while(grid[i - 3][j] == grid[i][j]) {
grid[i - 3][j] *= 2;
grid[i][j] = 0;
}
}
}
}
}
void all_go_up()
{
for(int i = 3; i > 0; i--) {
for(int j = 0; j < 4; j++) {
if(grid[i][j] > 0 && grid[i - 1][j] == 0) {
grid[i - 1][j] = grid[i][j];
grid[i][j] = 0;
}
for(int k = 3; k > 0; k--) {
if(grid[k][j] > 0 && grid[k - 1][j] == 0) {
grid[k - 1][j] = grid[k][j];
grid[k][j] = 0;
}
}
}
}
}
bool add_new_number(int num)
{
int n = rand() % 2 + 1;
int newnumber = 1 << n;
int r, c;
switch(num) {
case 1: //up
r = rand() % 2 + 2;
c = rand() % 4;
break;
case 2: //down
r = rand() % 2;
c = rand() % 4;
break;
case 3: //left
r = rand() % 4;
c = rand() % 2 + 2;
break;
case 4: //right
r = rand() % 4;
c = rand() % 2;
break;
}
do {
if(check_empty() == 1) {
if(grid[r][c] == 0) {
grid[r][c] = newnumber;
return false;
}
if(grid[r][c] != 0) {
switch(num) {
case 1: //up
r = rand() % 2 + 2;
c = rand() % 4;
break;
case 2: //down
r = rand() % 2;
c = rand() % 4;
break;
case 3: //left
r = rand() % 4;
c = rand() % 2 + 2;
break;
case 4: //right
r = rand() % 4;
c = rand() % 2;
break;
}
}
}
else {
return false;
}
} while(true);
}
I have some other functions to check whether the grid is full and so on. I also tried use some while() and for() to do this, too. But I do not know where I get wrong to code the function to test whether the game is over.
I hope I express my problem well. Hoping to get some suggestions to code the test_fail function without changing too much of my code. Thanks.

Answer 1

With all the respect, your code looks totally unreadable. Consider functional approach where you compose few smaller function to break down more complex problem. I am going to demonstrate this in Typescript but it would be very similar in C++. In this way the code is I believe self-explanatory.
type Board = number[][]
function isGameOver(board: Board) {
if (hasEmptySpace(board)) return false
return checkHorizontalGameOver(board) && checkVerticalGameOver(board)
}
function hasEmptySpace(board: Board) {
for (let r = 0; r < NUM_ROWS; r++) {
for (let c = 0; c < NUM_COLS; c++) {
if (board[r][c] === 0) return true
}
}
return false
}
function checkHorizontalGameOver(board: Board) {
for (let i = 0; i < NUM_ROWS; i++) {
for (let j = 0; j < NUM_COLS - 1; j++) {
if (board[i][j] === board[i][j + 1]) return false
}
}
return true
}
function checkVerticalGameOver(board: Board) {
for (let i = 0; i < NUM_ROWS - 1; i++) {
for (let j = 0; j < NUM_COLS; j++) {
if (board[i][j] === board[i + 1][j]) return false
}
}
return true
}
I understand it's 5 years ago as I am reading now and your skills in programming are far far better, but still - I will post it here for people who might come across this so it can possibly help them.