foo.c: In function 'main':
foo.c:9:3: warning: this 'if' clause does not guard... [-Wmisleading-indentation]
   if(ss(i)==1&&ss(n-i)==1)
   ^~
foo.c:11:4: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'if'
    printf("\n");
    ^~~~~~
foo.c:7:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d",&n);
  ^~~~~~~~~~~~~~

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