foo.cc: In function 'int main()':
foo.cc:6:5: warning: comparison of constant '1000000' with boolean expression is always true [-Wbool-compare]
 1<=n<=1000000&&-1000000<=a<=1000000;
 ~~~~^~~~~~~~~
foo.cc:6:2: warning: comparisons like 'X<=Y<=Z' do not have their mathematical meaning [-Wparentheses]
 1<=n<=1000000&&-1000000<=a<=1000000;
 ~^~~
foo.cc:6:27: warning: comparison of constant '1000000' with boolean expression is always true [-Wbool-compare]
 1<=n<=1000000&&-1000000<=a<=1000000;
                ~~~~~~~~~~~^~~~~~~~~
foo.cc:6:24: warning: comparisons like 'X<=Y<=Z' do not have their mathematical meaning [-Wparentheses]
 1<=n<=1000000&&-1000000<=a<=1000000;
                ~~~~~~~~^~~
foo.cc:6:14: warning: statement has no effect [-Wunused-value]
 1<=n<=1000000&&-1000000<=a<=1000000;
 ~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~

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