Wrong Answer
foo.cc: In function 'int main()':
foo.cc:64:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
scanf("%d%d%d%d",&n,&m,&a,&b);
~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
foo.cc:67:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
scanf("%d%d",&x,&y);
~~~~~^~~~~~~~~~~~~~
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