Compilare: user.cpp: In function ‘int main()’: user.cpp:15:41: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("saracsaurege.in","r",stdin); ^ user.cpp:16:43: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("saracsaurege.out","w",stdout); ^ user.cpp:20:25: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d",&n,&m); ^ user.cpp:23:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d ",&a[i]); ^ user.cpp:32:29: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d",&x,&y); ^ user.cpp:29:21: warning: ‘k’ may be used uninitialized in this function [-Wmaybe-uninitialized] int x,y,diff,sh,k,t; ^ user.cpp:33:9: warning: ‘l’ may be used uninitialized in this function [-Wmaybe-uninitialized] if (l != lg[y - x + 1]) { ^