<p>There is a strange printer with the following two special properties:</p>

<ul>
	<li>The printer can only print a sequence of <strong>the same character</strong> each time.</li>
	<li>At each turn, the printer can print new characters starting from and ending at any place and will cover the original existing characters.</li>
</ul>

<p>Given a string <code>s</code>, return <em>the minimum number of turns the printer needed to print it</em>.</p>

<p>&nbsp;</p>
<p><strong class="example">Example 1:</strong></p>

<pre>
<strong>Input:</strong> s = &quot;aaabbb&quot;
<strong>Output:</strong> 2
<strong>Explanation:</strong> Print &quot;aaa&quot; first and then print &quot;bbb&quot;.
</pre>

<p><strong class="example">Example 2:</strong></p>

<pre>
<strong>Input:</strong> s = &quot;aba&quot;
<strong>Output:</strong> 2
<strong>Explanation:</strong> Print &quot;aaa&quot; first and then print &quot;b&quot; from the second place of the string, which will cover the existing character &#39;a&#39;.
</pre>

<p>&nbsp;</p>
<p><strong>Constraints:</strong></p>

<ul>
	<li><code>1 &lt;= s.length &lt;= 100</code></li>
	<li><code>s</code> consists of lowercase English letters.</li>
</ul>

class Solution {
public:
    int dp[101][101];
    int f(string s,int l,int r){
        if(l>r) return 0;
        if(l==r) return 1;
        if(dp[l][r]!=-1) return dp[l][r];
        int ans=1+f(s,l+1,r);
        for(int j=l+1;j<=r;j++){
            if(s[j]==s[l]) ans=min(ans,f(s,l+1,j-1)+f(s,j,r));
        }
        // vector<vector<int>>v(26);
        // for(int i=l;i<=r;i++){
        //     int j=s[i]-'a';
        //     v[j].push_back(i);
        // }
        // int ans=INT_MAX;
        // for(int i=0;i<26;i++){
        //     if(v[i].size()==0) continue;
        //     for(int j=0;j<v[i].size();j++){
        //         for(int k=j;k<v[i].size();k++){
        //             int nl=v[i][j],nr=v[i][k];
        //             ans=min(ans,1+f(s,nl+1,nr-1)+f(s,l,nl-1)+f(s,nr+1,r));
        //         }
        //     }
        // }
        return dp[l][r]=ans;    
    }
    int strangePrinter(string s) {
        string s1="";char tmp=s[0];
        s1.push_back(tmp);
        for(int i=1;i<s.size();i++){
            if(s[i]!=tmp) s1.push_back(s[i]),tmp=s[i];
        }
        cout<<s1<<endl;
        memset(dp,-1,sizeof(dp));
        return f(s1,0,s1.size()-1);        
    }
};
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