/in/foo.cc: In function 'int main()':
/in/foo.cc:80:16: warning: format '%s' expects argument of type 'char*', but argument 2 has type 'char (*)[30]' [-Wformat=]
   scanf("%s",&s);
                ^
/in/foo.cc: In function 'bool Cut()':
/in/foo.cc:12:46: warning: array subscript is above array bounds [-Warray-bounds]
   int A=num[a[1][i]],B=num[a[2][i]],C=num[a[3][i]];
                                           ~~~^
/in/foo.cc: In function 'bool check()':
/in/foo.cc:28:46: warning: array subscript is above array bounds [-Warray-bounds]
   int A=num[a[1][i]],B=num[a[2][i]],C=num[a[3][i]];
                                           ~~~^
/in/foo.cc: In function 'void dfs(int, int, int)':
/in/foo.cc:28:46: warning: array subscript is above array bounds [-Warray-bounds]
   int A=num[a[1][i]],B=num[a[2][i]],C=num[a[3][i]];
                                           ~~~^
/in/foo.cc:60:25: warning: array subscript is above array bounds [-Warray-bounds]
      use[i]=true,num[a[y][x]]=i;
                      ~~~^
/in/foo.cc:62:26: warning: array subscript is above array bounds [-Warray-bounds]
      use[i]=false,num[a[y][x]]=-1;
                       ~~~^