Compilare: user.cpp: In function ‘void insert_update(int, int, int, int)’: user.cpp:56:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (end + 1 < s[nod].size()) { ^ user.cpp: In function ‘int main()’: user.cpp:97:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("vopsire.in", "r", stdin); ^ user.cpp:98:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("vopsire.out", "w", stdout); ^ user.cpp:100:30: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &n, &queries); ^ user.cpp:102:59: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d %d %d", &xs1[i], &xs2[i], &ys1[i], &ys2[i]); ^ user.cpp:107:33: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &xq[i], &yq[i]); ^