- Title effect: a sequence but do not know the specific numerical values are given some hints \ (t_i, L_i, r_i \) , \ (t_i = 0 \) representing the interval \ (L_i \) to \ (r_i \) ordered, \ (t_i = 1 \) was out of order
- Ideas: first construct an all-1 sequence, which can meet all \ (t_i = 1 \) case, then each \ (t_i = 0 \) first determines whether there is a section \ (t_i = 0 \) section contains, if it contains can not be met otherwise represented by an array of tags after the position of the element with an element should remain orderly, non-binding and has the disorder. for each \ (t_i = 0 \) found in its range without a constraint elements which can be changed to a disordered (if the interval has an element of disorder need not be changed)
#include<cstdio>
#include<cstring>
#include<queue>
#include<vector>
#include<iostream>
#include<algorithm>
#include<map>
#define ll long long
#define FOR(i,n) for(int i =1; i <= n;++i )
#define FOR0(i,n) for(int i =0; i < n;++i )
#define inf 0x3f3f3f3f
using namespace std;
const int maxn = 1010;
int n,m;
struct node{
int t,l,r;
}b[maxn];
int arr[maxn];
int vis[maxn];
int cmp(node x,node y){
if(x.t == y.t){
if(x.l == y.l){
return x.t==1?x.r < y.r:x.r>=y.r;
}
return x.t==1? x.l < y.l: x.l>=y.l ;
}
return x.t > y.t;
}
int main(){
cin >> n >> m;
for(int i=1;i<=m;++i){
cin >> b[i].t >> b[i].l >> b[i].r;
}
for(int i=1;i<=n;++i){
arr[i] = 1;
}
sort(b+1,b+1+m,cmp);
int r=0;
bool sign= false;
for(int i=1;i<=m;++i){
if(!b[i].t){
r = i;
break;
}
for(int j=b[i].l;j<b[i].r;++j){
vis[j] = 1;
}
}
if(r==0){
cout <<"YES" <<endl;
for(int i=1;i<=n;++i) cout << arr[i] << ' ';
cout << endl;
}else{
for(int i=r;i<=m;++i){
for(int j=1;j<r;++j){
if(b[j].l<=b[i].l && b[j].r>=b[i].r){
sign = true;
break;
}
}
if(sign) break;
int j;
for(j=b[i].l;j<b[i].r;++j){
if(vis[j]==-1) break;
else if(vis[j]==0){
vis[j] = -1;
arr[j] = arr[j+1]+1;
break;
}
}
if(j==b[i].r){
sign = true; break;
}
}
if(sign) cout << "NO" <<endl;
else{
cout <<"YES"<<endl;
for(int i=1;i<=n;++i){
cout << arr[i] << ' ';
}
cout << endl;
}
}
return 0;
}
- Summary: The general idea is greedy, but in the process \ (t_i = 0 \) when descending from the left end of the interval, otherwise the process will be covered later in front of the results (by hack out QAQ)