Compilare: main.cpp: In function 'int read()': main.cpp:60:60: warning: ignoring return value of 'char* fgets(char*, int, FILE*)', declared with attribute warn_unused_result [-Wunused-result] if (read_idx > BUF_SIZE) { fgets(reader, BUF_SIZE, stdin); read_idx = 0; } ^ main.cpp:69:60: warning: ignoring return value of 'char* fgets(char*, int, FILE*)', declared with attribute warn_unused_result [-Wunused-result] if (read_idx > BUF_SIZE) { fgets(reader, BUF_SIZE, stdin); read_idx = 0; } ^ main.cpp: In function 'int main()': main.cpp:99:33: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("scmax.in", "r", stdin); ^ main.cpp:100:35: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("scmax.out", "w", stdout); ^ main.cpp:102:18: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d ", &n); ^ main.cpp:106:21: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &a[i]); p.pb(a[i]); p_dp[i] = -1; ^