foo.cc: In function 'int main()':
foo.cc:50:11: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   50 |   mid = l + r >> 1;
      |         ~~^~~
foo.cc:39:9: warning: unused variable 'j' [-Wunused-variable]
   39 |  int i, j, l, r, mid, ans = 0;
      |         ^
foo.cc:40:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   40 |  scanf("%d", &n);
      |  ~~~~~^~~~~~~~~~
foo.cc:42:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   42 |   scanf("%d", &c[i]);
      |   ~~~~~^~~~~~~~~~~~~
foo.cc:43:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   43 |  scanf("%d", &m);
      |  ~~~~~^~~~~~~~~~
foo.cc:45:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   45 |   scanf("%d", &p[i]);
      |   ~~~~~^~~~~~~~~~~~~

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