foo.c: In function 'main':
foo.c:5:10: warning: unknown conversion type character 'y' in format [-Wformat=]
    5 |  scanf("%y1%y1",&x1,&x2);
      |          ^
foo.c:5:13: warning: unknown conversion type character 'y' in format [-Wformat=]
    5 |  scanf("%y1%y1",&x1,&x2);
      |             ^
foo.c:5:8: warning: too many arguments for format [-Wformat-extra-args]
    5 |  scanf("%y1%y1",&x1,&x2);
      |        ^~~~~~~~
foo.c:6:14: warning: unknown conversion type character 'y' in format [-Wformat=]
    6 |     printf("%y1",x1+x2);
      |              ^
foo.c:6:12: warning: too many arguments for format [-Wformat-extra-args]
    6 |     printf("%y1",x1+x2);
      |            ^~~~~

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