Compilare: user.cpp: In function ‘void fill(const int&, const int&, const int&, const int&)’: user.cpp:19:32: warning: suggest parentheses around comparison in operand of ‘&’ [-Wparentheses] if (0 < in && in <= n && 0 < jn & jn <= m && !a[in][jn]) ~~^~~~ user.cpp: In function ‘int main()’: user.cpp:27:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("colaj.in", "r", stdin); ^ user.cpp:28:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("colaj.out", "w", stdout); ^ user.cpp:31:32: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d", &nrd, &n, &m); ^ user.cpp:33:58: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d%d", &xSt[i], &ySt[i], &xDr[i], &yDr[i]); ^