foo.cc: In function 'void rotate(int)':
foo.cc:29:3: warning: this 'if' clause does not guard... [-Wmisleading-indentation]
   29 |   if(z)c[z][c[z][1]==y]=x;fa[x]=z;
      |   ^~
foo.cc:29:27: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'if'
   29 |   if(z)c[z][c[z][1]==y]=x;fa[x]=z;
      |                           ^~
foo.cc: In function 'void build(int&, int, int)':
foo.cc:53:12: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   53 |   int mid=l+r>>1;val[k]=a[mid];
      |           ~^~
foo.cc: In function 'int main()':
foo.cc:96:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   96 |     scanf("\n%s",s);
      |     ~~~~~^~~~~~~~~~

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