Compilare: main.cpp: In function 'void read()': main.cpp:21:44: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d %d %d ", &N, &S, &K1, &K2); ^ main.cpp:23:33: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d ", &ab[i].val); ^ main.cpp:26:24: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%s ", ch[0]); ^ main.cpp:32:24: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%s ", ch[1]); ^ main.cpp: In function 'int main()': main.cpp:43:35: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("grup.in", "r", stdin); ^ main.cpp:44:37: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("grup.out", "w", stdout); ^