foo.cc:1:30: warning: '-std=c++11' is not an option that controls warnings [-Wpragmas]
    1 | #pragma GCC diagnostic error "-std=c++11"
      |                              ^~~~~~~~~~~~
foo.cc:25:39: warning: bad option '-fwhole-program' to pragma 'optimize' [-Wpragmas]
   25 | #pragma GCC optimize("-fwhole-program")
      |                                       ^
foo.cc:32:41: warning: bad option '-fstrict-overflow' to pragma 'optimize' [-Wpragmas]
   32 | #pragma GCC optimize("-fstrict-overflow")
      |                                         ^
foo.cc:34:41: warning: bad option '-fcse-skip-blocks' to pragma 'optimize' [-Wpragmas]
   34 | #pragma GCC optimize("-fcse-skip-blocks")
      |                                         ^
foo.cc:48:51: warning: bad option '-funsafe-loop-optimizations' to pragma 'optimize' [-Wpragmas]
   48 | #pragma GCC optimize("-funsafe-loop-optimizations")
      |                                                   ^
foo.cc:55:14: warning: bad option '-fwhole-program' to attribute 'optimize' [-Wattributes]
   55 | int main(void)
      |              ^
foo.cc:55:14: warning: bad option '-fstrict-overflow' to attribute 'optimize' [-Wattributes]
foo.cc:55:14: warning: bad option '-fcse-skip-blocks' to attribute 'optimize' [-Wattributes]
foo.cc:55:14: warning: bad option '-funsafe-loop-optimizations' to attribute 'optimize' [-Wattributes]
foo.cc: In function 'int main()':
foo.cc:58:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   58 |     scanf("%d%d", &n, &front);
      |     ~~~~~^~~~~~~~~~~~~~~~~~~~
foo.cc:62:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   62 |         scanf("%d", &x);
      |         ~~~~~^~~~~~~~~~

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