uva12657纯双链模拟+白书代码（link函数是神器）

纯按结构体写的双向链，速度性能不够

#include<cstdio>
#include<cstring>
#include<stack>
#include<iostream>
#include<string>
using namespace std;
const int maxn = 100000 + 5;
struct node {
int i;
node* next;
node* last;
}nodes[maxn];
int n, m, t, a, b;
bool inv;
int main() {
while (scanf("%d%d", &n, &m)!=EOF)
{
memset(nodes, 0, sizeof(nodes));
nodes[0].next = &nodes[1];
nodes[n + 1].last = &nodes
;
for (int i = 1; i <= n; i++) {
nodes[i].i = i;
nodes[i].next = &nodes[i + 1];
nodes[i].last = &nodes[i - 1];
}
inv = 0;
while (m--) {
scanf("%d", &t);

if (inv && (t == 1 || t == 2)) {
t = 3 - t;
}
if (t == 4) {
inv = !inv;
}
else {
scanf("%d%d", &a, &b);
}
node* aq = nodes[a].last;
node* ap = nodes[a].next;
node* bq = nodes[b].last;
node* bp = nodes[b].next;
if (t == 1) {
aq->next = ap;
ap->last = aq;
nodes[a].last = bq;
nodes[a].next = nodes + b;
bq->next = nodes + a;
nodes[b].last = nodes + a;
}
else if (t == 2) {
aq->next = ap;
ap->last = aq;
nodes[a].last = nodes + b;
nodes[a].next = bp;
nodes[b].next = nodes + a;
bp->last = nodes + a;
}
else if (t == 3) {
aq->next = nodes + b;
ap->last = nodes + b;
bq->next = nodes + a;
bp->last = nodes + a;
nodes[a].next = bp;
nodes[a].last = bq;
nodes[b].next = ap;
nodes[b].last = aq;
}
else if (t == 4) {
inv = ~inv;
}
}
// node head=nodes[0];
int index=0;
long long ans=0;
// printf("%d\n", inv);
if(0==inv){
for (node* i = nodes; i->next; i = i->next){
// printf("%d\t",i->i );
if(index%2==1)ans+=i->i;
index++;
}
}
else{
for (node* i = nodes+n+1; i->last; i = i->last){
// printf("%d\t",i->i );
if(index%2==1)ans+=i->i;
index++;
}
}
printf("\n%lld\n",ans);
}
return 0;
}

白书代码

#include<cstdio>
#include<algorithm>

using namespace std;
const int maxn = 100000 + 6;
int left[maxn],right[maxn],inv;
void link(int l,int r){
right[l]=r;left[r]=l;
}
int main() {
int n;

int m,kase=0;
while(scanf("%d%d",&n,&m)==2){
for(int i=1;i<=n;i++){
left[i]=i-1;
right[i]=(i+1)%(n+1);
}
int b=0;

right[0]=1;left[0]=n;

int op,x,y,inv=0;
while(m--){
scanf("%d",&op);
if(op==4)inv=!inv;
else{
scanf("%d%d",&x,&y);
// if(op==3&&right[y]==x)swap(x,y);
if(op!=3&&inv)op=3-op;
if(op==1&&x==left[y])continue;
if(op==2&&x==right[y])continue;
int lx=left[x],rx=right[x],ly=left[y],ry=right[y];
if(op==1){
link(lx,rx);link(ly,x);link(x,y);
lx=left[x],rx=right[x],ly=left[y],ry=right[y];
}
else if(op==2){
link(lx,rx);link(y,x);link(x,ry);
}
else if(op==3){
if(right[x]==y){link(lx,y);link(y,x);link(x,ry);}
else{link(lx,y);link(y,rx);link(ly,x);link(x,ry);}
}
}
}
long long ans=0;
for(int i=1;i<=n;i++){
b=right[b];
if(i%2==1) ans+=b;
}
if(inv&&n%2==0) ans=(long long)n*(n+1)/2-ans;
printf("Case %d: %lld\n",++kase,ans );
}
return 0;
}