foo.c: In function 'main':
foo.c:7:2: warning: implicit declaration of function 'sacnf'; did you mean 'sscanf'? [-Wimplicit-function-declaration]
  sacnf("%d %d",&n,&k);
  ^~~~~
  sscanf
/tmp/ccCrz1de.o: In function `main':
foo.c:(.text.startup+0x26): undefined reference to `sacnf'
collect2: error: ld returned 1 exit status

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