Given s1, s2, s3, find whether s3 is formed by the interleaving of s1 and s2.
For example,
Given:
s1 ="aabcc"
,
s2 ="dbbca"
,When s3 =
"aadbbcbcac"
, return true.
When s3 ="aadbbbaccc"
, return false.
二维DP问题,二维矩阵f的大小为:s1.length() * s2.length(); f[i][j] 的状态只和f[i - 1][j] 和 f[i][j - 1]相关。public boolean 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; } boolean[][] f = new boolean[len1 + 1][len2 + 1]; f[0][0] = true; for (int i = 1; i <= len1; i++) { f[i][0] = f[i - 1][0] && s3.charAt(i - 1) == s1.charAt(i - 1); } for (int j = 1; j <= len2; j++) { f[0][j] = f[0][j - 1] && s2.charAt(j - 1) == s3.charAt(j - 1); } for (int i = 1; i <= len1; i++) { for (int j = 1; j <= len2; j++) { int len = i + j; char c1 = s1.charAt(i - 1); char c2 = s2.charAt(j - 1); char c3 = s3.charAt(len - 1); f[i][j] = (c1 == c3 && f[i - 1][j]) || (c2 == c3 && f[i][j - 1]); } } return f[len1][len2]; }
Interleaving String,布布扣,bubuko.com
原文地址:http://blog.csdn.net/u010378705/article/details/28884121