foo.cc:2:30: warning: '-std=c++11' is not an option that controls warnings [-Wpragmas]
    2 | #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:57:12: warning: bad option '-fwhole-program' to attribute 'optimize' [-Wattributes]
   57 |     matrix(){
      |            ^
foo.cc:57:12: warning: bad option '-fstrict-overflow' to attribute 'optimize' [-Wattributes]
foo.cc:57:12: warning: bad option '-fcse-skip-blocks' to attribute 'optimize' [-Wattributes]
foo.cc:57:12: warning: bad option '-funsafe-loop-optimizations' to attribute 'optimize' [-Wattributes]
foo.cc:61:51: warning: bad option '-fwhole-program' to attribute 'optimize' [-Wattributes]
   61 | matrix operator *(const matrix &x, const matrix &y){
      |                                                   ^
foo.cc:61:51: warning: bad option '-fstrict-overflow' to attribute 'optimize' [-Wattributes]
foo.cc:61:51: warning: bad option '-fcse-skip-blocks' to attribute 'optimize' [-Wattributes]
foo.cc:61:51: warning: bad option '-funsafe-loop-optimizations' to attribute 'optimize' [-Wattributes]
foo.cc:73:29: warning: bad option '-fwhole-program' to attribute 'optimize' [-Wattributes]
   73 | matrix __pow(matrix a, int k){
      |                             ^
foo.cc:73:29: warning: bad option '-fstrict-overflow' to attribute 'optimize' [-Wattributes]
foo.cc:73:29: warning: bad option '-fcse-skip-blocks' to attribute 'optimize' [-Wattributes]
foo.cc:73:29: warning: bad option '-funsafe-loop-optimizations' to attribute 'optimize' [-Wattributes]
foo.cc:87:13: warning: bad option '-fwhole-program' to attribute 'optimize' [-Wattributes]
   87 | signed main(){
      |             ^
foo.cc:87:13: warning: bad option '-fstrict-overflow' to attribute 'optimize' [-Wattributes]
foo.cc:87:13: warning: bad option '-fcse-skip-blocks' to attribute 'optimize' [-Wattributes]
foo.cc:87:13: warning: bad option '-funsafe-loop-optimizations' to attribute 'optimize' [-Wattributes]

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