判断子序列

class Solution {
public:
    bool isSubsequence(string s, string t) {
        int i,m=0;
        for(i=0;i<size(t);i++)
        {
            if(t[i]==s[m])
            {
                m++;
                if(m==size(s)) break;
            }
        }
        return m==size(s);        
    }
};