foo.c: In function 'main':
foo.c:13:9: warning: 'a' may be used uninitialized [-Wmaybe-uninitialized]
   13 |         printf("%d", a + 1);
      |         ^~~~~~~~~~~~~~~~~~~
foo.c:5:19: note: 'a' was declared here
    5 |         int n, k, a,m;
      |                   ^

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