用数组写感觉萌萌哒啊，本题可以写个link函数，更加方便
1 #include<iostream> 2 #include<cstdio> 3 #include<cstring> 4 using namespace std; 5 const int maxx=100010; 6 int r[maxx],l[maxx]; 7 int n,m; 8 long long ans; 9 int main() 10 { 11 int cnt=0; 12 while(~scanf("%d%d",&n,&m)) 13 { 14 ans=0; 15 for(int i=1;i<=n;i++) 16 { 17 r[i]=i+1; 18 l[i]=i-1; 19 } 20 r[0]=1; 21 r[n]=0; 22 l[1]=0; 23 l[0]=n; 24 bool f=0; 25 while(m--) 26 { 27 int op,x,y; 28 scanf("%d",&op); 29 if(op==4) f=!f; 30 else 31 { 32 scanf("%d%d",&x,&y); 33 if((f==0&&op==1)||(f==1&&op==2)) 34 { 35 r[l[x]]=r[x]; 36 l[r[x]]=l[x]; 37 l[x]=l[y]; 38 r[l[y]]=x; 39 r[x]=y; 40 l[y]=x; 41 } 42 else if((f==0&&op==2)||(f==1&&op==1)) 43 { 44 r[l[x]]=r[x]; 45 l[r[x]]=l[x]; 46 r[x]=r[y]; 47 l[r[y]]=x; 48 l[x]=y; 49 r[y]=x; 50 } 51 else if(op==3) 52 { 53 if(r[x]==y) 54 { 55 r[x]=r[y]; 56 l[r[y]]=x; 57 r[l[x]]=y; 58 l[y]=l[x]; 59 l[x]=y; 60 r[y]=x; 61 } 62 else if(l[x]==y) 63 { 64 r[l[y]]=x; 65 l[x]=l[y]; 66 l[r[x]]=y; 67 r[y]=r[x]; 68 r[x]=y; 69 l[y]=x; 70 } 71 else 72 { 73 r[l[x]]=y; 74 l[r[x]]=y; 75 r[l[y]]=x; 76 l[r[y]]=x; 77 swap(r[x],r[y]); 78 swap(l[x],l[y]); 79 } 80 } 81 } 82 } 83 if(f==0) 84 { 85 for(int p=r[0],i=1;p!=0&&i<=n;p=r[p],i++) 86 if(i%2==1) ans+=p; 87 } 88 else 89 { 90 for(int p=l[0],i=1;p!=0&&i<=n;p=l[p],i++) 91 if(i%2==1) ans+=p; 92 } 93 printf("Case %d: %lld ",++cnt,ans); 94 } 95 }