Compilare: user.cpp: In function ‘void solve()’: user.cpp:132:39: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j = 0; j < V[i].size(); ++ j) ^ user.cpp: In function ‘void read()’: user.cpp:102:34: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d %d", &n, &m, &k); ^ user.cpp:108:34: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &a[i][j]); ^ user.cpp: In function ‘int main()’: user.cpp:157:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &t); ^