foo.cc:3:20: error: expected unqualified-id before numeric constant
 int x,y,k,a[10000],1[30000];
                    ^
foo.cc: In function 'int main()':
foo.cc:10:3: error: 'b' was not declared in this scope
   b[i]=0;
   ^
foo.cc:21:7: error: 'b' was not declared in this scope
    if(b[i]>b[j])
       ^

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