/in/foo.c: In function 'add':
/in/foo.c:10:17: error: 'aj' undeclared (first use in this function); did you mean 'j'?
   10 |             if (aj] >a[j + 1])
      |                 ^~
      |                 j
/in/foo.c:10:17: note: each undeclared identifier is reported only once for each function it appears in
/in/foo.c:10:19: error: expected ')' before ']' token
   10 |             if (aj] >a[j + 1])
      |                ~  ^
      |                   )
/in/foo.c:10:19: error: expected statement before ']' token
/in/foo.c:10:13: warning: this 'if' clause does not guard... [-Wmisleading-indentation]
   10 |             if (aj] >a[j + 1])
      |             ^~
/in/foo.c:10:21: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'if'
   10 |             if (aj] >a[j + 1])
      |                     ^
/in/foo.c:10:21: error: expected expression before '>' token
/in/foo.c:10:30: error: expected statement before ')' token
   10 |             if (aj] >a[j + 1])
      |                              ^
/in/foo.c: In function 'main':
/in/foo.c:25:30: error: 'a' undeclared (first use in this function)
   25 |                  scanf("%c",&a[i]);
      |                              ^
/in/foo.c:27:9: warning: unused variable 'n' [-Wunused-variable]
   27 |     int n= strlen(a);
      |         ^
/in/foo.c:22:10: warning: unused variable 'str' [-Wunused-variable]
   22 |     char str[100];
      |          ^~~