foo.cc: In function 'void dfs(int)':
foo.cc:45:23: warning: suggest parentheses around assignment used as truth value [-Wparentheses]
for (int i=head[u]; i=0; i=G[i].pre)
~^~
foo.cc: In function 'int main()':
foo.cc:62:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
scanf("%lld",&z);
~~~~~^~~~~~~~~~~
/tmp/ccAyuHU5.o: In function `main':
foo.cc:(.text.startup+0x8d): undefined reference to `anode()'
collect2: error: ld returned 1 exit status
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xhs20071024 LV 4
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