Compilare: user.cpp: In function ‘void fill2(int, int)’: user.cpp:31:23: warning: statement has no effect [-Wunused-value] for(it; it != vec[v[l][c]].end() ; ++it) ^ user.cpp: In function ‘int main()’: user.cpp:70:19: warning: statement has no effect [-Wunused-value] for(it; it != vec[z[i]].end() ; ++it) ^ user.cpp:43:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("zone2.in", "r", stdin); ^ user.cpp:44:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("zone2.out", "w", stdout); ^ user.cpp:45:34: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d\n", &n, &m, &k); ^ user.cpp:47:30: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%s", a[i] + 1); ^