Color Length UVA - 1625

记录在两个序列当中每个字母的起始位置和结束位置，然后按照紫书思路进行递推，注意一个技巧，将一个空字符分别放到两个字符串的开始，并且二维数组的[0][0]位置的值记为0，具体实现见如下代码：

#include<iostream>
#include<vector>
#include<string>
#include<set>
#include<stack>
#include<queue>
#include<map>
#include<algorithm>
#include<cmath>
#include<iomanip>
#include<cstring>
#include<sstream>
#include<cstdio>
#include<deque>
using namespace std;

int T;
string s1, s2;
int start1[30], start2[30];
int end1[30], end2[30];
int n, m;

int Distance(int index1,int index2){
int amount = 0;
for (char var = 'A'; var <= 'Z'; var++){
int ind = var - 'A';
if ((start1[ind] && start1[ind] <= index1 || start2[ind] && start2[ind] <= index2)
&&(end1[ind]>index1||end2[ind]>index2)) amount++;
}
return amount;
}

int main(){
cin >> T;
while (T--){
cin >> s1 >> s2;
memset(start1, 0, sizeof(start1));
memset(start2, 0, sizeof(start2));
memset(end1, 0, sizeof(end1));
memset(end2, 0, sizeof(end2));
n = s1.size(); m = s2.size();
s1 = " " + s1;
s2 = " " + s2;
for (int i = 1; i <= n; i++){
int index1 = s1[i] - 'A';
if (start1[index1] == 0) start1[index1] = i;
end1[index1] = i;
}
for (int i = 1; i <= m; i++){
int index2 = s2[i] - 'A';
if (start2[index2] == 0) start2[index2] = i;
end2[index2] = i;
}
int arr[500][500];
arr[0][0] = 0;
for (int i = 0; i <= n; i++){
for (int j = 0; j <= m; j++){
if(i||j) arr[i][j] = 1 << 20;
if (i) arr[i][j] = min(arr[i][j], arr[i - 1][j] + Distance(i - 1, j));
if (j) arr[i][j] = min(arr[i][j], arr[i][j - 1] + Distance(i, j - 1));
}
}
cout << arr
[m] << endl;
}
return 0;
}