Compilare: user.cpp: In constructor ‘IntervalTrees::IntervalTrees(const std::vector<int>&)’: user.cpp:19:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < nums.size(); ++i) { ^ user.cpp: In member function ‘int IntervalTrees::Update(int, int)’: user.cpp:51:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while (position < sums.size()) { ^ user.cpp:55:3: warning: no return statement in function returning non-void [-Wreturn-type] } ^ user.cpp: In function ‘int main()’: user.cpp:74:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("arbint.in","r",stdin); ^ user.cpp:75:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("arbint.out","w",stdout); ^ user.cpp:79:28: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &nums[i]); ^ user.cpp:82:36: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &queries[i].type); ^ user.cpp:84:53: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &queries[i].x, &queries[i].y); ^ user.cpp:86:35: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &queries[i].x); ^ user.cpp:78:5: warning: ‘nums_number’ may be used uninitialized in this function [-Wmaybe-uninitialized] for (int i = 0; i < nums_number; ++i) { ^ user.cpp:81:5: warning: ‘queries_number’ may be used uninitialized in this function [-Wmaybe-uninitialized] for (int i = 0; i < queries_number; ++i) { ^