Compilare: main.cpp: In function 'int main()': main.cpp:60:15: warning: unused variable 'j' [-Wunused-variable] int i,dir,j,xf,yf; ^ main.cpp:61:43: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf(in,"%d %d %d %d",&xs,&ys,&n,&l); ^ main.cpp:68:29: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf(in,"%d",&dir); ^ main.cpp:121:42: warning: 'yf' may be used uninitialized in this function [-Wmaybe-uninitialized] fprintf(out,"%d\n",a[xs][ys]-a[xf][yf]+1); ~~~~~~~~^ main.cpp:121:42: warning: 'xf' may be used uninitialized in this function [-Wmaybe-uninitialized]