Compilare: user.cpp: In function ‘void build_rmq()’: user.cpp:27:35: warning: suggest parentheses around ‘-’ in operand of ‘&’ [-Wparentheses] lg[i] = lg[i-1] + int((i&i-1)==0); ^ user.cpp:35:19: warning: suggest parentheses around ‘-’ inside ‘<<’ [-Wparentheses] if(j+(1<<i-1)<=buff && h[rmq[i-1][j+(1<<i-1)]]<h[rmq[i][j]]) ^ user.cpp:35:50: warning: suggest parentheses around ‘-’ inside ‘<<’ [-Wparentheses] if(j+(1<<i-1)<=buff && h[rmq[i-1][j+(1<<i-1)]]<h[rmq[i][j]]) ^ user.cpp:36:41: warning: suggest parentheses around ‘-’ inside ‘<<’ [-Wparentheses] rmq[i][j] = rmq[i-1][j+(1<<i-1)]; ^ user.cpp: In function ‘int main()’: user.cpp:52:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("lca.in", "r", stdin); ^ user.cpp:53:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("lca.out", "w", stdout); ^ user.cpp:56:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&n,&m); ^ user.cpp:58:23: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&a); ^ user.cpp:66:28: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&a,&b); ^