foo.cc: In function 'int main()':
foo.cc:10:21: error: expected ';' before 'if'
   10 |                 a[x]
      |                     ^
      |                     ;
   11 |                 if(a[x]==1)ans++;
      |                 ~~   
foo.cc:10:20: warning: statement has no effect [-Wunused-value]
   10 |                 a[x]
      |                 ~~~^

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