Compilare: main.cpp: In function 'int main()': main.cpp:83:37: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen ("pensula.in", "r", stdin); ^ main.cpp:84:39: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen ("pensula.out", "w", stdout); ^ main.cpp:85:39: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d %d %d", &n, &M, &Q, &C); ^ main.cpp:87:23: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &t[i]); ^ main.cpp: In function 'void subtask1()': main.cpp:60:7: warning: 'i' may be used uninitialized in this function [-Wmaybe-uninitialized] i = u[i]; ~~^~~~~~