foo.cc: In member function 'void seg::build(int, int, int, int)':
foo.cc:17:13: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   17 |   int m = l + r >> 1;
      |           ~~^~~
foo.cc: In member function 'void seg::update(int, int, ll, int, int, int)':
foo.cc:29:13: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   29 |   int m = l + r >> 1;
      |           ~~^~~
foo.cc: In member function 'll seg::query(int, int, int, int, int, ll)':
foo.cc:39:13: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   39 |   int m = l + r >> 1;
      |           ~~^~~
foo.cc: In function 'void merge(seg, seg, seg, int, int, int)':
foo.cc:50:12: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   50 |  int m = l + r >> 1;
      |          ~~^~~
foo.cc: In function 'void build(int, int, int)':
foo.cc:60:12: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   60 |  int m = l + r >> 1;
      |          ~~^~~
foo.cc: In function 'void update(int, int, int, int, ll, int, int, int)':
foo.cc:72:12: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   72 |  int m = l + r >> 1;
      |          ~~^~~
foo.cc: In function 'll query(int, int, int, int, int, int, int, ll)':
foo.cc:82:12: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   82 |  int m = l + r >> 1; ll ret = 0;
      |          ~~^~~
foo.cc:82:25: warning: unused variable 'ret' [-Wunused-variable]
   82 |  int m = l + r >> 1; ll ret = 0;
      |                         ^~~
foo.cc: In function 'int main()':
foo.cc:90:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   90 |  scanf("%d", &n);
      |  ~~~~~^~~~~~~~~~
foo.cc:93:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   93 |   scanf("%d", &m);
      |   ~~~~~^~~~~~~~~~
foo.cc:96:9: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   96 |    scanf("%d%d%d", &x1, &y1, &w);
      |    ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
foo.cc:100:9: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  100 |    scanf("%d%d%d%d", &x1, &y1, &x2, &y2);
      |    ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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