foo.cc: In function 'void dts::main()':
foo.cc:42:26: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
                     scanf("%c",&c[i][j]);
                     ~~~~~^~~~~~~~~~~~~~~
foo.cc:40:13: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
             for (int i=0;i<n;scanf("\n"),i++)
             ^~~

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