Compilare: user.cpp: In function ‘void build()’: user.cpp:18:50: warning: suggest parentheses around ‘-’ inside ‘<<’ [-Wparentheses] v[i][j]=min(v[i-1][j], v[i-1][j+(1<<i-1)]); ^ user.cpp:9:9: warning: unused variable ‘t’ [-Wunused-variable] int t; ^ user.cpp: In function ‘int main()’: user.cpp:31:29: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fi,"%d %d",&n,&m); ^ user.cpp:33:33: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fi,"%d",&v[0][i]); ^ user.cpp:39:32: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fi,"%d%d",&x,&y); ^