Compilare: main.cpp: In function 'void dfs(int, int)': main.cpp:25:12: warning: statement has no effect [-Wunused-value] for(pas;pas<=len;pas<<=1); ^ main.cpp:27:12: warning: statement has no effect [-Wunused-value] for(pas;pas;pas>>=1) ^ main.cpp: In function 'int main()': main.cpp:42:38: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("spiridusi.in","r",stdin); ^ main.cpp:43:40: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("spiridusi.out","w",stdout); ^ main.cpp:45:25: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &n,&c); ^ main.cpp:47:27: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &s[i]); ^ main.cpp:49:27: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &p[i]); ^ main.cpp:51:29: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &x,&y); ^