AcWing 2816. 判断子序列

Posted 2022-02-09 MangataTS

题目连接

https://www.acwing.com/problem/content/2818/

思路

双指针扫描，一个指向A，一个指向B，然后匹配成功就都往后移否则，b往后移动，注意一下边界情况就行，我在这RE了好几次

#include<bits/stdc++.h>
using namespace std;
#define ll long long
#define mod 1000000009
#define endl "\\n"
#define PII pair<int,int>

int dx[4]=0,-1,0,1,dy[4]=-1,0,1,0;

ll ksm(ll a,ll b) 
	ll ans = 1;
	for(;b;b>>=1LL) 
		if(b & 1) ans = ans * a % mod;
		a = a * a % mod;
	
	return ans;


ll lowbit(ll x)return -x & x;

const int N = 2e6+10;
int n,m,a[N],b[N];

int main()

	cin>>n>>m;
	for(int i = 1;i <= n; ++i) cin>>a[i];
	for(int j = 1;j <= m; ++j) cin>>b[j];
	int l = 1,r = 1;
	while(true) 
		if(a[l] == b[r])
			if(l == n)
				puts("Yes");
				return 0;
			
			l++;
			r++;
		else r++;
		if(l > n || r > m) break;
	
	puts("No");
	
	return 0;