Compilare: main.cpp: In function 'int main()': main.cpp:34:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(v[y].size() < x) ~~~~~~~~~~~~^~~ main.cpp:20:16: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&n); ^ main.cpp:24:18: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&x); ^ main.cpp:29:16: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&q); ^ main.cpp:33:24: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d",&x,&y); ^