foo.cc: In function 'int main()':
foo.cc:61:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
61 | scanf("%d%d",&n,&m);
| ~~~~~^~~~~~~~~~~~~~
foo.cc:64:9: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
64 | scanf("%d",&a[i][j]);
| ~~~~~^~~~~~~~~~~~~~~
foo.cc:65:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
65 | scanf("%d%d%d%d",&sx,&sy,&gx,&gy);
| ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~
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