foo.cc: In function 'void Concat(char*, char*)':
foo.cc:12:9: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
   12 |         for (int k = i-1; k < j+i - 1; k++)
      |         ^~~
foo.cc:14:17: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
   14 |                 printf("%s", c);
      |                 ^~~~~~

[Hydro](https://hydro.ac)提供评测服务