原题地址:https://leetcode-cn.com/problems/interleaving-string/description/
题目描述:
给定三个字符串 s1, s2, s3, 验证 s3 是否是由 s1 和 s2 交错组成的。
示例 1:
输入: s1 = "aabcc", s2 = "dbbca", s3 = "aadbbcbcac"
输出: true
示例 2:
输入: s1 = "aabcc", s2 = "dbbca", s3 = "aadbbbaccc"
输出: false
解题方案:
又是dp的题目,好难啊。。。参考链接:https://blog.youkuaiyun.com/xygy8860/article/details/47102283
class Solution {
public:
bool isInterleave(string s1, string s2, string s3) {
int len1 = s1.length();
int len2 = s2.length();
int len3 = s3.length();
if(len1 + len2 != len3)
return false;
bool f[len1 + 1][len2 + 1];
f[0][0] = true;//第一个设置为true
for(int i = 0; i < len1 + 1; i++){
for(int j = 0; j < len2 + 1; j++){
//i>0,j>0的条件是摒除i=0j=0的值
if(j > 0){
f[i][j] = f[i][j - 1] && (s3[i + j - 1] == s2[j - 1]);
}
if(i > 0){
f[i][j] = f[i][j] || ( f[i - 1][j] && (s3[i + j - 1] == s1[i - 1]));
}
}
}
return f[len1][len2];
}
};