Compilare: user.cpp: In function ‘bool check(int, int, int)’: user.cpp:28:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(p2 + k - 1 >= poz[query[i] - 'a'].size()) ~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~ user.cpp: In function ‘int main()’: user.cpp:50:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j = 0; j < poz[i].size(); ++j) ~~^~~~~~~~~~~~~~~ user.cpp:40:32: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fin, "%d%d", &n, &q); ^