This commit is contained in:
krahets
2024-05-06 14:40:36 +08:00
parent 7e7eb6047a
commit 5c7d2c7f17
54 changed files with 3456 additions and 215 deletions
@@ -104,7 +104,31 @@ Observing the state transition equation, solving $dp[i, j]$ depends on the solut
=== "C++"
```cpp title="edit_distance.cpp"
[class]{}-[func]{editDistanceDP}
/* Edit distance: Dynamic programming */
int editDistanceDP(string s, string t) {
int n = s.length(), m = t.length();
vector<vector<int>> dp(n + 1, vector<int>(m + 1, 0));
// State transition: first row and first column
for (int i = 1; i <= n; i++) {
dp[i][0] = i;
}
for (int j = 1; j <= m; j++) {
dp[0][j] = j;
}
// State transition: the rest of the rows and columns
for (int i = 1; i <= n; i++) {
for (int j = 1; j <= m; j++) {
if (s[i - 1] == t[j - 1]) {
// If the two characters are equal, skip these two characters
dp[i][j] = dp[i - 1][j - 1];
} else {
// The minimum number of edits = the minimum number of edits from three operations (insert, remove, replace) + 1
dp[i][j] = min(min(dp[i][j - 1], dp[i - 1][j]), dp[i - 1][j - 1]) + 1;
}
}
}
return dp[n][m];
}
```
=== "Java"
@@ -289,7 +313,34 @@ For this reason, we can use a variable `leftup` to temporarily store the solutio
=== "C++"
```cpp title="edit_distance.cpp"
[class]{}-[func]{editDistanceDPComp}
/* Edit distance: Space-optimized dynamic programming */
int editDistanceDPComp(string s, string t) {
int n = s.length(), m = t.length();
vector<int> dp(m + 1, 0);
// State transition: first row
for (int j = 1; j <= m; j++) {
dp[j] = j;
}
// State transition: the rest of the rows
for (int i = 1; i <= n; i++) {
// State transition: first column
int leftup = dp[0]; // Temporarily store dp[i-1, j-1]
dp[0] = i;
// State transition: the rest of the columns
for (int j = 1; j <= m; j++) {
int temp = dp[j];
if (s[i - 1] == t[j - 1]) {
// If the two characters are equal, skip these two characters
dp[j] = leftup;
} else {
// The minimum number of edits = the minimum number of edits from three operations (insert, remove, replace) + 1
dp[j] = min(min(dp[j - 1], dp[j]), leftup) + 1;
}
leftup = temp; // Update for the next round of dp[i-1, j-1]
}
}
return dp[m];
}
```
=== "Java"