foo.cc:23:39: warning: bad option '-fwhole-program' to pragma 'optimize' [-Wpragmas]
 #pragma GCC optimize("-fwhole-program")
                                       ^
foo.cc:32:41: warning: bad option '-fcse-skip-blocks' to pragma 'optimize' [-Wpragmas]
 #pragma GCC optimize("-fcse-skip-blocks")
                                         ^
foo.cc:46:51: warning: bad option '-funsafe-loop-optimizations' to pragma 'optimize' [-Wpragmas]
 #pragma GCC optimize("-funsafe-loop-optimizations")
                                                   ^
foo.cc:77:37: warning: bad option '-fwhole-program' to attribute 'optimize' [-Wattributes]
 inline void insert(int x,int y,int z) {
                                     ^
foo.cc:77:37: warning: bad option '-fcse-skip-blocks' to attribute 'optimize' [-Wattributes]
foo.cc:77:37: warning: bad option '-funsafe-loop-optimizations' to attribute 'optimize' [-Wattributes]
foo.cc:81:38: warning: bad option '-fwhole-program' to attribute 'optimize' [-Wattributes]
 inline void insert2(int x,int y,int z) {
                                      ^
foo.cc:81:38: warning: bad option '-fcse-skip-blocks' to attribute 'optimize' [-Wattributes]
foo.cc:81:38: warning: bad option '-funsafe-loop-optimizations' to attribute 'optimize' [-Wattributes]
foo.cc:86:29: warning: bad option '-fwhole-program' to attribute 'optimize' [-Wattributes]
 inline void dfs(int x,int fa) {
                             ^
foo.cc:86:29: warning: bad option '-fcse-skip-blocks' to attribute 'optimize' [-Wattributes]
foo.cc:86:29: warning: bad option '-funsafe-loop-optimizations' to attribute 'optimize' [-Wattributes]
foo.cc:103:40: warning: bad option '-fwhole-program' to attribute 'optimize' [-Wattributes]
 inline void merge(int x,int fa,int mark) {
                                        ^
foo.cc:103:40: warning: bad option '-fcse-skip-blocks' to attribute 'optimize' [-Wattributes]
foo.cc:103:40: warning: bad option '-funsafe-loop-optimizations' to attribute 'optimize' [-Wattributes]
foo.cc:114:25: warning: bad option '-fwhole-program' to attribute 'optimize' [-Wattributes]
 bool cmp(edge2 a,edge2 b) {
                         ^
foo.cc:114:25: warning: bad option '-fcse-skip-blocks' to attribute 'optimize' [-Wattributes]
foo.cc:114:25: warning: bad option '-funsafe-loop-optimizations' to attribute 'optimize' [-Wattributes]
foo.cc:117:45: warning: bad option '-fwhole-program' to attribute 'optimize' [-Wattributes]
 inline int dfs2(int x,int fa,int ban,int val) {
                                             ^
foo.cc:117:45: warning: bad option '-fcse-skip-blocks' to attribute 'optimize' [-Wattributes]
foo.cc:117:45: warning: bad option '-funsafe-loop-optimizations' to attribute 'optimize' [-Wattributes]
foo.cc:133:17: warning: bad option '-fwhole-program' to attribute 'optimize' [-Wattributes]
 bool check(int x) {
                 ^
foo.cc:133:17: warning: bad option '-fcse-skip-blocks' to attribute 'optimize' [-Wattributes]
foo.cc:133:17: warning: bad option '-funsafe-loop-optimizations' to attribute 'optimize' [-Wattributes]
foo.cc:143:43: warning: bad option '-fwhole-program' to attribute 'optimize' [-Wattributes]
 __attribute__((optimize("-O3"))) int main() {
                                           ^
foo.cc:143:43: warning: bad option '-fcse-skip-blocks' to attribute 'optimize' [-Wattributes]
foo.cc:143:43: warning: bad option '-funsafe-loop-optimizations' to attribute 'optimize' [-Wattributes]
foo.cc: In function 'int main()':
foo.cc:144:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d%d",&n,&m);
     ~~~~~^~~~~~~~~~~~~~
foo.cc:147:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d%d%d",&x,&y,&z);
         ~~~~~^~~~~~~~~~~~~~~~~~~

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