Compilare: user.cpp: In function ‘void calc(int)’: user.cpp:25:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i = 0; i < tati[pos].size(); i++) { ^ user.cpp: In function ‘int main()’: user.cpp:35:12: warning: unused variable ‘j’ [-Wunused-variable] int i, j; ^ user.cpp:36:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("hektor.in", "r", stdin); ^ user.cpp:37:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("hektor.out", "w", stdout); ^ user.cpp:38:41: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d %d %d", &N, &M, &A, &B); ^ user.cpp:40:30: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%u", &cost[i]); ^ user.cpp:44:31: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &a, &b); ^