链接:http://www.lintcode.com/zh-cn/problem/interleaving-string/
给出三个字符串:s1、s2、s3,判断s3是否由s1和s2交叉构成。
您在真实的面试中是否遇到过这个题?
Yes
样例
比如 s1 = "aabcc" s2 = "dbbca"
- 当 s3 = "aadbbcbcac",返回 true.
- 当 s3 = "aadbbbaccc", 返回 false.
class Solution {
public:
/**
* @param s1: A string
* @param s2: A string
* @param s3: A string
* @return: Determine whether s3 is formed by interleaving of s1 and s2
*/
bool isInterleave(string &s1, string &s2, string &s3) {
if(s1.length()<=0 && s2.length()<=0 && s3.length()<=0)
return true;
vector<vector<bool>> dp(s1.length()+1,vector<bool>(s2.length()+1,false));
for(int i=1;i<=s1.length();i++)
{
if(s1[i-1]==s3[i-1])
{
dp[i][0]=true;
}
else
{
break;
}
}
for(int i=1;i<=s2.length();i++)
{
if(s2[i-1]==s3[i-1])
{
dp[0][i]=true;
}
else
{
break;
}
}
for(int i=1;i<=s1.length();i++)
{
for(int j=1;j<=s2.length();j++)
{
if(s1[i-1]==s3[i+j-1] && dp[i-1][j])
{
dp[i][j]=true;
}
if(s2[j-1]==s3[i+j-1] && dp[i][j-1])
{
dp[i][j]=true;
}
}
}
return dp[s1.length()][s2.length()];
}
};