foo.c: In function 'main':
foo.c:7:17: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[101]' [-Wformat=]
    7 |         scanf("%s %s",&a,&b);
      |                ~^     ~~
      |                 |     |
      |                 |     char (*)[101]
      |                 char *
foo.c:7:20: warning: format '%s' expects argument of type 'char *', but argument 3 has type 'char (*)[101]' [-Wformat=]
    7 |         scanf("%s %s",&a,&b);
      |                   ~^     ~~
      |                    |     |
      |                    |     char (*)[101]
      |                    char *
foo.c:8:13: warning: implicit declaration of function 'strlen' [-Wimplicit-function-declaration]
    8 |         len=strlen(a);
      |             ^~~~~~
foo.c:2:1: note: include '<string.h>' or provide a declaration of 'strlen'
    1 | #include <stdio.h>
  +++ |+#include <string.h>
    2 | int main()
foo.c:8:13: warning: incompatible implicit declaration of built-in function 'strlen' [-Wbuiltin-declaration-mismatch]
    8 |         len=strlen(a);
      |             ^~~~~~
foo.c:8:13: note: include '<string.h>' or provide a declaration of 'strlen'
foo.c:5:15: warning: unused variable 'j' [-Wunused-variable]
    5 |         int i,j,len;
      |               ^

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