foo.cc: In function 'void sh()':
foo.cc:7:9: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
    7 |         for(int i=1;i<=n;i++)
      |         ^~~
foo.cc:13:17: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
   13 |                 swap(n,m);
      |                 ^~~~
foo.cc: In function 'void ni()':
foo.cc:19:9: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
   19 |         for(int i=1;i<=n;i++)
      |         ^~~
foo.cc:25:17: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
   25 |                 swap(n,m);
      |                 ^~~~
foo.cc: In function 'void sh_p()':
foo.cc:30:9: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
   30 |         for(int i=1;i<=n;i++)
      |         ^~~
foo.cc:36:17: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
   36 |                 memcpy(a,b,sizeof(b));
      |                 ^~~~~~
foo.cc: In function 'void ch_z()':
foo.cc:40:9: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
   40 |         for(int i=1;i<=n;i++)
      |         ^~~
foo.cc:46:17: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
   46 |                 memcpy(a,b,sizeof(b));
      |                 ^~~~~~
foo.cc: In function 'int main()':
foo.cc:62:34: warning: statement is a reference, not call, to function 'sh_p' [-Waddress]
   62 |                         case 'C':sh_p;break;
      |                                  ^~~~
foo.cc:62:34: warning: statement has no effect [-Wunused-value]
foo.cc:63:34: warning: statement is a reference, not call, to function 'ch_z' [-Waddress]
   63 |                         case 'D':ch_z;
      |                                  ^~~~
foo.cc:63:34: warning: statement has no effect [-Wunused-value]

[Hydro](https://hydro.ac)提供评测服务