foo.cc: In function 'int main()':
foo.cc:37:14: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
     cin >> s + 1;
            ~~^~~
foo.cc:35:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d", &n);
     ~~~~~^~~~~~~~~~

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