JavaScript数据结构7——串的模拟匹配

串的模拟匹配是使用常规思路对串进行字串匹配

function String(string) {
    this.data = string;
}
String.prototype.index =function(t){
    var i=0;j=0;
    while(i<this.data.length&&j<t.data.length){
        if(this.data[i]==t.data[j]){
            i++;j++;
        }else{
            i = i-j+1;j=0;
        }
    }
    if(j>=t.data.length){
        return i-t.data.length;
    }else{
        return -1;
    }
}
var s = new String('google');
var s1 = new String('og');
var s2 = new String('gl');
var s3 = new String('e');
var s4 = new String('g');
var s5 = new String('aaaa');
console.info(s.index(s1));
console.info(s.index(s2));
console.info(s.index(s3));
console.info(s.index(s4));
console.info(s.index(s5));

输出

2
3
5
0
-1