Compilare: main.cpp: In function 'void write()': main.cpp:70:37: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(!c[l+1][pos] && a[l+1][pos]<nr) ~~~~~~~~~~~^~~ main.cpp: In function 'void read()': main.cpp:23:42: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf(in,"%d\n%d %d %d",&p,&n,&st,&dr); ^ main.cpp:26:31: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf(in,"%d",&a[i][j]); ^