Compilare: user.cpp: In function ‘int main()’: user.cpp:139:33: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("soc2.in","r",stdin); ^ user.cpp:140:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("soc2.out","w",stdout); ^ user.cpp:142:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&n,&m); ^ user.cpp:144:30: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&value[i]); ^ user.cpp:146:28: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&a,&b); ^ user.cpp: In function ‘void Reconstitute(TreeNode*)’: user.cpp:131:22: warning: ‘which’ may be used uninitialized in this function [-Wmaybe-uninitialized] seen[which]=1; ^