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Remember the Word,LA3942(Trie树+DP)

Trie树基础题,记录下代码。

#include <cstdio>
#include <cstring>

#define MaxNode 4005*100
#define NodeSize 26
#define MOD 20071027

char givenword[300005];
int ans[300005];
int next[MaxNode][NodeSize];
class Trie{
    public:
        int val[MaxNode];
        int sz;
        Trie(){
            sz = 1;     //初始时有一个根结点
            memset(next[0], 0, sizeof(next[0]));
        }
        int idx(char ch){
            return ch - 'a';
        }
        void insert(char *s, int v){
            int len = strlen(s);
            int d = 0;
            for(int i = 0; i < len; ++i){
                int _idx = idx(s[i]);
                if(!next[d][_idx]){
                    memset(next[sz],0,sizeof(next[sz]));
                    val[sz] = 0;
                    next[d][_idx] = sz++;
                }
                d = next[d][_idx];
            }
            val[d] = v;
        }
        void query(char *s,int pos){
            int len = strlen(s);
            int d = 0;
            for(int i = 0; i < len; ++i){
                int _idx = idx(s[i]);
                if(!next[d][_idx])  return;
                d = next[d][_idx];
                if(val[d]){
                    ans[pos] += ans[pos+i+1];
                    if(ans[pos] > MOD) ans[pos] -= MOD;
                }
            }
            return;
        }
};


int main()
{
    int S;
    int Case = 1;
    while(scanf("%s",givenword)!=EOF){
        int len = strlen(givenword);
        memset(ans,0,(len+1)*sizeof(int));
        ans[len] = 1;
        scanf("%d",&S);
        char tstr[105];
        Trie trie;
        for(int i = 0;i < S;++i){
            scanf("%s",tstr);
            trie.insert(tstr,1);
        }
        for(int i = len-1; i >= 0; --i){
            trie.query(&givenword[i],i);
        }
        printf("Case %d: ",Case++);
        printf("%d\n",ans[0]);
    }
    return 0;
}