Compilare: user.cpp: In function ‘int main()’: user.cpp:40:31: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("ab.in", "r", stdin); ^ user.cpp:41:33: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("ab.out", "w", stdout); ^ user.cpp:44:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] for(scanf("%d", &tCases); tCases > 0; tCases--) { ^ user.cpp:45:34: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d %d", &N, &M, &K); ^ user.cpp:46:54: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] for(int i = 1; i <= K; i++) scanf("%d", &Cost[i]); ^ user.cpp:47:30: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &lastEdge[1]); ^ user.cpp:49:32: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &lastEdge[i]); ^