foo.c: In function 'Compare':
foo.c:27:7: warning: suggest parentheses around assignment used as truth value [-Wparentheses]
    if(i=0 && b[i][j]==1 && b[i+1][j]==1)
       ^
foo.c:30:7: warning: suggest parentheses around assignment used as truth value [-Wparentheses]
    if(i=m-1 && b[i][j]==1 && b[i-1][j]==1)
       ^
foo.c: In function 'main':
foo.c:9:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d",&m,&n);
  ^~~~~~~~~~~~~~~~~~~
foo.c:13:4: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    scanf("%d",&a[i][j]);
    ^~~~~~~~~~~~~~~~~~~~
foo.c: In function 'Compare':
foo.c:30:31: warning: array subscript is below array bounds [-Warray-bounds]
    if(i=m-1 && b[i][j]==1 && b[i-1][j]==1)
                              ~^~~~~

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