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#include<cstdio>
#include<cstring>
#include<algorithm>
#include<iostream>
#include<queue>
#include<map>
#include<stack>
#include<cmath>
#include<set>
#include<bitset>
#include<complex>
#include<assert.h>
#define inc(i,l,r) for(int i=l;i<=r;i++)
#define dec(i,l,r) for(int i=l;i>=r;i--)
#define link(x) for(edge *j=h[x];j;j=j->next)
#define mem(a) memset(a,0,sizeof(a))
#define ll long long
#define eps 1e-8
#define succ(x) (1<<x)
#define lowbit(x) (x&(-x))
#define sqr(x) ((x)*(x))
#define NM 100005
#define nm 255
using namespace std;
const double pi=acos(-1);
const ll inf=998244353;
ll read(){
ll x=0,f=1;char ch=getchar();
while(!isdigit(ch)){if(ch=='-')f=-1;ch=getchar();}
while(isdigit(ch))x=x*10+ch-'0',ch=getchar();
return f*x;
}
int n,m,b[NM][26],d[nm][nm][nm],_x,len[5];
char s[NM],_s[5],str[4][255];
int main(){
n=read();m=read();
scanf("%s",s+1);
inc(j,0,25)b[n+1][j]=n+1;
dec(i,n,0){
inc(j,0,25)b[i][j]=b[i+1][j];
if(i<n)b[i][s[i+1]-'a']=i+1;
}
d[0][0][0]=0;
while(m--){
scanf("%s",_s);
if(_s[0]=='+'){
_x=read();scanf("%s",_s);
char ch=_s[0];
len[_x]++;str[_x][len[_x]]=ch;
if(_x==1){
int i=len[_x];
inc(j,0,len[2])inc(k,0,len[3]){
d[i][j][k]=n+1;
if(i)d[i][j][k]=min(d[i][j][k],b[d[i-1][j][k]][str[1][i]-'a']);
if(j)d[i][j][k]=min(d[i][j][k],b[d[i][j-1][k]][str[2][j]-'a']);
if(k)d[i][j][k]=min(d[i][j][k],b[d[i][j][k-1]][str[3][k]-'a']);
}
}else if(_x==2){
int j=len[_x];
inc(i,0,len[1])inc(k,0,len[3]){
d[i][j][k]=n+1;
if(i)d[i][j][k]=min(d[i][j][k],b[d[i-1][j][k]][str[1][i]-'a']);
if(j)d[i][j][k]=min(d[i][j][k],b[d[i][j-1][k]][str[2][j]-'a']);
if(k)d[i][j][k]=min(d[i][j][k],b[d[i][j][k-1]][str[3][k]-'a']);
}
}else{
int k=len[_x];
inc(i,0,len[1])inc(j,0,len[2]){
d[i][j][k]=n+1;
if(i)d[i][j][k]=min(d[i][j][k],b[d[i-1][j][k]][str[1][i]-'a']);
if(j)d[i][j][k]=min(d[i][j][k],b[d[i][j-1][k]][str[2][j]-'a']);
if(k)d[i][j][k]=min(d[i][j][k],b[d[i][j][k-1]][str[3][k]-'a']);
}
}
if(d[len[1]][len[2]][len[3]]<=n)puts("YES");else puts("NO");
}else{
_x=read();
len[_x]--;
if(d[len[1]][len[2]][len[3]]<=n)puts("YES");else puts("NO");
}
}
return 0;
}
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