Compilare: user.cpp: In function ‘int main()’: user.cpp:59:26: warning: unused variable ‘k’ [-Wunused-variable] int i, j, room, cnt, k, newi, newj, change; ^ user.cpp:59:29: warning: unused variable ‘newi’ [-Wunused-variable] int i, j, room, cnt, k, newi, newj, change; ^ user.cpp:59:35: warning: unused variable ‘newj’ [-Wunused-variable] int i, j, room, cnt, k, newi, newj, change; ^ user.cpp:59:41: warning: unused variable ‘change’ [-Wunused-variable] int i, j, room, cnt, k, newi, newj, change; ^ user.cpp:57:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("castel.in", "r", stdin); ^ user.cpp:58:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("castel.out", "w", stdout); ^ user.cpp:61:35: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d", &n, &m, &room); ^ user.cpp:64:37: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &grid[i][j]); ^