Compilare: main.c: In function 'main': main.c:63:5: warning: ignoring return value of 'fscanf', declared with attribute warn_unused_result [-Wunused-result] fscanf(read, "%d", &n); ^~~~~~~~~~~~~~~~~~~~~~ main.c:66:9: warning: ignoring return value of 'fscanf', declared with attribute warn_unused_result [-Wunused-result] fscanf(read, "%li", &x); ^~~~~~~~~~~~~~~~~~~~~~~ main.c: In function 'ciur': main.c:11:13: warning: iteration 999998 invokes undefined behavior [-Waggressive-loop-optimizations] if(b[i] == 0) ~^~~ main.c:9:5: note: within this loop for(int i = 2; i <= 1000000; i++) ^~~