HNUSTOJ-1543 字符串的运算再现

#pragma GCC diagnostic error "-std=c++11"
#include <bits/stdc++.h>
#define _ ios_base::sync_with_stdio(0);cin.tie(0);
#include <typeinfo>


using namespace std;
const int N =  100000 + 5;

char s[N], t[N];


void Init(int * a, int n){ for(int i = 0; i < n; i++) a[i] = 0;}
int Work(){
    int lens = strlen(s), lent = strlen(t);
    set<int> next[26];
    int vis[26]; Init(vis, 26);
    for(int i = 0 ; i < lens; i++)
        vis[s[i] - ‘a‘] = 1, next[s[i]-‘a‘].insert(i);

    for(int i = 0; i < lent; i++) if(!vis[t[i]-‘a‘]) return -1;

    int cur = 0, k = 1;

    set<int>::iterator it;

    for(int i = 0; i < lent; i++){
        int p = t[i] - ‘a‘;
        if((it = next[p].lower_bound(cur)) != next[p].end()) cur = (*it) + 1;
        else cur = 0, k++, i--;
    }
    return k;
}
int main(){ _
    while(cin >> s >> t){
        cout << Work() << endl;
    }
}