/in/foo.c: In function 'main':
/in/foo.c:6:23: error: expected ';' before 'int'
    6 |         scanf("%d",&n)
      |                       ^
      |                       ;
    7 |         int yanghui[20][20]={0};
      |         ~~~            
/in/foo.c:9:17: error: 'yanghui' undeclared (first use in this function)
    9 |                 yanghui[i][0]=1;
      |                 ^~~~~~~
/in/foo.c:9:17: note: each undeclared identifier is reported only once for each function it appears in