dp+dfs
class Solution {
public:
void dfs(vector<string>&res,vector<bool>&dp,vector<vector<bool>>p,string s,string temp_s,int index){
if(index==s.length()){
res.push_back(temp_s);
return;
}
for(int i=index;i<s.length();++i){
if(dp[i+1]==0||p[index][i]==0)continue;
string str=s.substr(index,i-index+1);
if(!temp_s.empty())str=" "+str;
dfs(res,dp,p,s,temp_s+str,i+1);
}
}
vector<string> wordBreak(string s, vector<string>& wordDict) {
int n=s.length();
vector<string>res;
vector<bool>dp(n,false);
vector<vector<bool>>p(n,vector<bool>(n,false));
dp[0]=true;
p[0][0]=true;
for(int i=0;i<n;++i){
for(int j=i;j>=0;--j){
string str=s.substr(j,i-j+1);
int t=count(wordDict.begin(),wordDict.end(),str);
if(t&&dp[j]){
p[j][i]=true;
dp[i+1]=true;
}
}
}
if(dp[n])
dfs(res,dp,p,s,"",0);
return res;
}
};