Compilare: user.cpp: In function ‘int main()’: user.cpp:59:38: 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); ^ user.cpp:60:40: 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); ^ user.cpp:62:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&n,&B); ^ user.cpp:64:29: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&spir[i]); ^ user.cpp:66:26: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&p[i]); ^ user.cpp:69:28: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&a,&b); ^ user.cpp: In function ‘void dfs(int)’: user.cpp:47:34: warning: ‘sol’ may be used uninitialized in this function [-Wmaybe-uninitialized] solmax = max(solmax, rmq[sol + (1 << prep[nr - sol + 1]) - 1][prep[nr - sol + 1]] + sp2[nr] - sp2[sol + (1 << prep[nr - sol + 1]) - 1]); ^