Compilare: user.c:4:19: warning: built-in function ‘log’ declared as non-function [enabled by default] int r[nmax][logn],log[nmax]; ^ user.c: In function ‘main’: user.c:15:11: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fin,"%d%d",&n,&m); ^ user.c:19:15: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fin,"%d",&r[i][0]); ^ user.c:24:15: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fin,"%d%d",&a,&b); ^