二叉树的序遍历

 1 #include<cstdio>
 2 int n,a,b,tr[60],v[60];
 3 inline void xx(int x){if(!tr[x]) return;printf("%d ",tr[x]);xx(x*2);xx(x*2+1);}
 4 inline void zx(int x){if(!tr[x]) return;zx(x*2);printf("%d ",tr[x]);zx(x*2+1);}
 5 inline void hx(int x){if(!tr[x]) return;hx(x*2);hx(x*2+1);printf("%d ",tr[x]);}
 6 int main(){
 7     scanf("%d",&n);tr[1]=v[1]=1;
 8     for(int i=1;i<=n;i++){
 9         scanf("%d%d",&a,&b);
10         tr[v[i]*2]=a;tr[v[i]*2+1]=b;
11         v[a]=v[i]*2;v[b]=v[i]*2+1;
12     }
13     xx(1);printf("\n");
14     zx(1);printf("\n");
15     hx(1);printf("\n");
16     return 0;
17 }