Compilare: user.cpp: In function ‘void precompute()’: user.cpp:54:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j=0; j<v.size(); ++j) ^ user.cpp: In function ‘int main()’: user.cpp:72:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("tri2.in", "r", stdin); ^ user.cpp:73:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("tri2.out", "w", stdout); ^ user.cpp:75:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &n); ^ user.cpp:78:40: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &a[i].x, &a[i].y); ^ user.cpp:82:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &q); ^ user.cpp:85:42: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d", &id1, &id2, &id3); ^