区间DP UVA 11584 Partitioning by Palindromes

题目传送门

 1 /*
 2     题意:给一个字符串,划分成尽量少的回文串
 3     区间DP:状态转移方程:dp[i] = min (dp[i], dp[j-1] + 1); dp[i] 表示前i个字符划分的最少回文串,
 4             如果s[j] 到 s[i]是回文串,那么可以从dp[j-1] + 1递推过来
 5 */
 6 #include <cstdio>
 7 #include <cstring>
 8 #include <algorithm>
 9 #include <cmath>
10 using namespace std;
11
12 const int MAXN = 1e3 + 10;
13 const int INF = 0x3f3f3f3f;
14 int dp[MAXN];
15 char s[MAXN];
16
17 bool ok(int l, int r)   {
18     while (l < r)   {
19         if (s[l] != s[r])   return false;
20         l++;    r--;
21     }
22     return true;
23 }
24
25 int main(void)  {       //UVA 11584 Partitioning by Palindromes
26     int T;  scanf ("%d", &T);
27     while (T--) {
28         scanf ("%s", s + 1);
29         int len = strlen (s + 1);
30         memset (dp, 0, sizeof (dp));
31         for (int i=1; i<=len; ++i)  {
32             dp[i] = i;
33             for (int j=1; j<=i; ++j) {
34                 if (ok (j, i))  {
35                     dp[i] = min (dp[i], dp[j-1] + 1);
36                 }
37             }
38         }
39
40         printf ("%d\n", dp[len]);
41     }
42
43     return 0;
44 }
时间: 2024-10-09 23:05:37

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