foo.c: In function 'main':
foo.c:40:34: warning: format '%d' expects argument of type 'int', but argument 2 has type 'size_t' {aka 'long unsigned int'} [-Wformat=]
   40 |         if(n==3)        printf("%d",strlen(a));
      |                                 ~^  ~~~~~~~~~
      |                                  |  |
      |                                  |  size_t {aka long unsigned int}
      |                                  int
      |                                 %ld
foo.c:6:15: warning: unused variable 'm' [-Wunused-variable]
    6 |         int n,m,k[100]={0},i=0,j;
      |               ^

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