Compilare: main.cpp: In function 'int main()': main.cpp:27:36: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("sumdiv2.in","r",stdin); ^ main.cpp:28:38: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("sumdiv2.out","w",stdout); ^ main.cpp:30:19: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&n); ^ main.cpp:35:28: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&x,&y); ^ main.cpp: In function 'void eratostene()': main.cpp:21:27: warning: iteration 1000002 invokes undefined behavior [-Waggressive-loop-optimizations] s[i]=s[i-1]+ciur[i]+1; ~~~~~~^ main.cpp:20:14: note: within this loop for(i=1;i<=NMAX;i++) ^