foo.cc: In function 'void cre()':
foo.cc:24:15: warning: suggest explicit braces to avoid ambiguous 'else' [-Wdangling-else]
             if(ht[j].pa==0)
               ^
foo.cc:23:9: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
         for(int j=i-1;j>=1;j--)
         ^~~
foo.cc:37:13: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
             ht[p1].pa=i;
             ^~
foo.cc: In function 'int main()':
foo.cc:104:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(int i=0;i<chi.length();i++)
                 ~^~~~~~~~~~~~~

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