foo.cc: In function 'int main()':
foo.cc:23:8: warning: unused variable 'p' [-Wunused-variable]
   23 |  int n,p;
      |        ^
foo.cc:24:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   24 |  scanf("%d",&n);
      |  ~~~~~^~~~~~~~~
foo.cc:31:9: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   31 |    scanf("%d",&x);
      |    ~~~~~^~~~~~~~~
foo.cc:56:10: warning: 'bian' may be used uninitialized in this function [-Wmaybe-uninitialized]
   56 |   s[++ll]=bian;
      |   ~~~~~~~^~~~~

Found 7 testcases.
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