Compilare: user.cpp: In function ‘int main()’: user.cpp:43:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for( i=0;i<M.size()&&k<=n-1;i++) ^ user.cpp:33:27: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%d%d",&n,&m); ^ user.cpp:36:47: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%d%d%d",&mc.x,&mc.y,&mc.cst); ^