foo.c: In function 'main':
foo.c:23:10: warning: too many arguments for format [-Wformat-extra-args]
   23 |   printf("%d%d+%d%d=%d\n",a1,a1,b1,b2,n,m);
      |          ^~~~~~~~~~~~~~~~
foo.c:6:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    6 |  scanf("%d%d%d%d",&a1,&a2,&b1,&b2);
      |  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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