Language: C++

int main(void) {
int h, w;
cin >> h >> w;
string board[50];
for (int i = 0; i < h; ++i) cin >> board[i];
const int dx[8] = {1, 0, -1, 0, 1, -1, -1, 1};
const int dy[8] = {0, 1, 0, -1, 1, 1, -1, -1};
for (int i = 0; i < h; ++i) {
for (int j = 0; j < w; ++j) {
if (board[i][j] == ’#’) continue;
int num = 0;
for (int d = 0; d < 8; ++ d) {
const int ni = i + dy[d];
const int nj = j + dx[d];
if (ni < 0 or h <= ni) continue;
if (nj < 0 or w <= nj) continue;
if (board[ni][nj] == ’#’) num++;
}
board[i][j] = char(num + ’0’);
}
}
for (int i = 0; i < h; ++i) cout << board[i] << endl;
return 0;
}

Compiler output:
a.cc:10:20: error: extended character ’ is not valid in an identifier
   10 | if (board[i][j] == ’#’) continue;
      |                    ^
a.cc:10:21: error: stray '#' in program
   10 | if (board[i][j] == ’#’) continue;
      |                     ^
a.cc:10:22: error: extended character ’ is not valid in an identifier
   10 | if (board[i][j] == ’#’) continue;
      |                      ^
a.cc:17:22: error: extended character ’ is not valid in an identifier
   17 | if (board[ni][nj] == ’#’) num++;
      |                      ^
a.cc:17:23: error: stray '#' in program
   17 | if (board[ni][nj] == ’#’) num++;
      |                       ^
a.cc:17:24: error: extended character ’ is not valid in an identifier
   17 | if (board[ni][nj] == ’#’) num++;
      |                        ^
a.cc:19:26: error: extended character ’ is not valid in an identifier
   19 | board[i][j] = char(num + ’0’);
      |                          ^
a.cc:19:26: error: extended character ’ is not valid in an identifier
a.cc: In function 'int main()':
a.cc:3:1: error: 'cin' was not declared in this scope
    3 | cin >> h >> w;
      | ^~~
a.cc:4:1: error: 'string' was not declared in this scope
    4 | string board[50];
      | ^~~~~~
a.cc:5:36: error: 'board' was not declared in this scope
    5 | for (int i = 0; i < h; ++i) cin >> board[i];
      |                                    ^~~~~
a.cc:10:5: error: 'board' was not declared in this scope
   10 | if (board[i][j] == ’#’) continue;
      |     ^~~~~
a.cc:10:20: error: '\U00002019' was not declared in this scope
   10 | if (board[i][j] == ’#’) continue;
      |                    ^
a.cc:10:21: error: expected ')' before '\U00002019'
   10 | if (board[i][j] == ’#’) continue;
      |    ~                ^~
      |                     )
a.cc:17:5: error: 'board' was not declared in this scope
   17 | if (board[ni][nj] == ’#’) num++;
      |     ^~~~~
a.cc:17:22: error: '\U00002019' was not declared in this scope
   17 | if (board[ni][nj] == ’#’) num++;
      |                      ^
a.cc:17:23: error: expected ')' before '\U00002019'
   17 | if (board[ni][nj] == ’#’) num++;
      |    ~                  ^~
      |                       )
a.cc:19:1: error: 'board' was not declared in this scope
   19 | board[i][j] = char(num + ’0’);
      | ^~~~~
a.cc:19:26: error: '\U000020190\U00002019' was not declared in this scope
   19 | board[i][j] = char(num + ’0’);
      |                          ^~~
a.cc:22:29: error: 'cout' was not declared in this scope
   22 | for (int i = 0; i < h; ++i) cout << board[i] << endl;
      |                             ^~~~
a.cc:22:37: error: 'board' was not declared in this scope
   22 | for (int i = 0; i < h; ++i) cout << board[i] << endl;
      |                                     ^~~~~
a.cc:22:49: error: 'endl' was not declared in this scope
   22 | for (int i = 0; i < h; ++i) cout << board[i] << endl;
      |                                                 ^~~~