【模板】KMP算法

KMP算法用于字符串匹配

/*KMP*/
#include<stdio.h>
#include<string.h>
char s1[1000005],s2[1005];//s1 为待匹配串，s2为模板串
int nxt[1005],n,m;
int main()
{
    scanf("%s%s",s1+1,s2+1);
    n = strlen(s1+1); m = strlen(s2+1);
    nxt[1] = 0; int i,k = 0;
    for(i=2;i<=m;i++)
    {
        while(k>0&&s2[k+1]!=s2[i]) k = nxt[k];
        if(s2[k+1]==s2[i]) k++;
        nxt[i] = k;
    }
    k = 0;
    for(i=1;i<=n;i++)
    {
        while(k>0&&s2[k+1]!=s1[i]) k = nxt[k];
        if(s2[k+1]==s1[i]) k++;
        if(k==m) printf("%d
",i-m+1),k=nxt[k];
    }
    for(i=1;i<=m;i++) printf("%d ",nxt[i]);
    return 0;
}