本题和动态规划:115.不同的子序列?相比,其实就是两个字符串都可以删除了,情况虽说复杂一些,但整体思路是不变的。
583. 两个字符串的删除操作 - 力扣(LeetCode)
class Solution {
public int minDistance(String word1, String word2) {
int len1 = word1.length();
int len2 = word2.length();
//以i-1为结尾的word1 和以j-1为结尾的word2 相等的最少操作为dp[i][j]
int [][] dp = new int[len1+1][len2+1];
for (int i = 0; i < word1.length() + 1; i++) dp[i][0] = i;
for (int j = 0; j < word2.length() + 1; j++) dp[0][j] = j;
for(int i = 1;i<=len1;i++){
for(int j = 1;j<=len2;j++){
if (word1.charAt(i-1) == word2.charAt(j-1)) {
dp[i][j] = dp[i - 1][j - 1];
} else {
dp[i][j] = Math.min(dp[i - 1][j] + 1, dp[i][j - 1] + 1);
}
}
}
return dp[len1][len2];
}
}
在上面几道题做完之后,这个还挺简单的
class Solution {
public int minDistance(String word1, String word2) {
int len1 = word1.length();
int len2 = word2.length();
//以i-1结尾的word1和以j-1为word相等,最少操作次数是dp[i][j]
int [][] dp = new int[len1+1][len2+1];
for (int i = 1; i <= len1; i++) {
dp[i][0] = i;
}
for (int j = 1; j <= len2; j++) {
dp[0][j] = j;
}
for(int i = 1;i<=len1;i++){
for(int j =1;j<=len2;j++){
if(word1.charAt(i-1)==word2.charAt(j-1)){
dp[i][j] = dp[i-1][j-1];
}else{
dp[i][j] = Math.min(Math.min(dp[i - 1][j - 1]+1, dp[i][j - 1]+1), dp[i - 1][j]+1) ;
}
}
}
return dp[len1][len2];
}
}
二刷总结