Compilare: main.cpp: In function 'bool check(int, int)': main.cpp:30:8: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(l >= app[c].size()) { ~~^~~~~~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:56:28: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf(in, "%d%d", &n, &q); ^ main.cpp:57:21: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf(in, "%s", s); ^ main.cpp:69:22: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf(in, "%s", a); ^