【POJ 3461】 Oulipo

【题目链接】

点击打开链接

【算法】

KMP

【代码】

#include <algorithm>
#include <bitset>
#include <cctype>
#include <cerrno>
#include <clocale>
#include <cmath>
#include <complex>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <ctime>
#include <deque>
#include <exception>
#include <fstream>
#include <functional>
#include <limits>
#include <list>
#include <map>
#include <iomanip>
#include <ios>
#include <iosfwd>
#include <iostream>
#include <istream>
#include <ostream>
#include <queue>
#include <set>
#include <sstream>
#include <stdexcept>
#include <streambuf>
#include <string>
#include <utility>
#include <vector>
#include <cwchar>
#include <cwctype>
#include <stack>
#include <limits.h>
using namespace std;
#define MAXW 10010
#define MAXT 1000010

int T,l1,l2;
char s1[MAXW],s2[MAXT];
int next[MAXW];

template <typename T> inline void read(T &x) {
        int f = ; x = ;
        char c = getchar();
        for (; !isdigit(c); c = getchar()) { if (c == '-') f = -f; }
        for (; isdigit(c); c = getchar()) x = (x << ) + (x << ) + c - '';
        x *= f;
}

template <typename T> inline void write(T x) {
    if (x < ) { putchar('-'); x = -x; }
    if (x > ) write(x/);
    putchar(x%+'');
}

template <typename T> inline void writeln(T x) {
    write(x);
    puts("");
}

inline void getnext() {
        int i,pos;
        next[] = ;
        for (i = ; i <= l1; i++) {
                pos = next[i-];
                while (pos >  && s1[pos+] != s1[i]) pos = next[pos];
                if (s1[pos+] == s1[i]) next[i] = pos + ;
                else next[i] = ;
        }
}

inline void kmp() {
        int i,pos=,sum=;
        for (i = ; i <= l2; i++) {
                while (pos >  && s2[i] != s1[pos+]) pos = next[pos];
                if (s2[i] == s1[pos+]) pos++;
                else pos = ;
                if (pos == l1) sum++;
        }
        writeln(sum);
}

int main() {

        read(T);
        while (T--) {
                scanf("%s%s",s1+,s2+);
                l1 = strlen(s1+); l2 = strlen(s2+);
                getnext();
                kmp();
        }

        return ;

}