Compilare: user.cpp: In function ‘int main()’: user.cpp:13:27: 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:14:42: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] for (i=1;i<=n;i++) {fscanf(f,"%d",&x);v[x]=1;} ^ user.cpp:15:42: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] for (i=1;i<=m;i++) {fscanf(f,"%d",&x);if (v[x]==1){v[x]=3;if (mx<x) mx=x;}else v[x]=2;} ^