修改

adam1iu · Aug 21, 2018 · e3e5d9b · e3e5d9b
1 parent d38643a
commit e3e5d9b
Showing 1 changed file with 18 additions and 23 deletions.
diff --git a/数据结构与算法/算法题总结.md b/数据结构与算法/算法题总结.md
@@ -1129,22 +1129,22 @@ public:
     vector<vector<int>> subsets(vector<int>& nums) {
         vector<int> subset;
         vector<vector<int>> res;
-        subsets(nums,0,res,subset);
+        dfs(nums,0,res,subset);
         return res;
     }
 
 private:
-    void subsets(const vector<int> &nums,int idx,vector<vector<int>> &res,vector<int> subset){
+    void dfs(const vector<int> &nums,int idx,vector<vector<int>> &res,vector<int> subset){
         if(idx < 0) return;
         else if(idx == nums.size()){
             res.push_back(subset);
             return;
         }
 
         subset.push_back(nums[idx]);
-        subsets(nums,idx + 1,res,subset);
+        dfs(nums,idx + 1,res,subset);
         subset.pop_back();
-        subsets(nums,idx + 1,res,subset);
+        dfs(nums,idx + 1,res,subset);
     }
 };
 ```
@@ -11575,26 +11575,25 @@ public:
 class Solution {
 public:
     vector<vector<int>> combinationSum(vector<int>& candidates, int target) {
-        if(candidates.size() == 0)  return vector<vector<int>>();
-
         std::sort(candidates.begin(),candidates.end());
         vector<vector<int>> res;
         vector<int> set;
-        combinationSum(candidates,target,0,res,set);
+        dfs(candidates,target,0,res,set);
 
         return res;
     }
 private:
-    void combinationSum(const vector<int> &candidates,int target,int idx,vector<vector<int>> &res,vector<int> &set){
-        if(idx == candidates.size()){
-            if(!target)   res.push_back(set);
+    void dfs(const vector<int> &candidates,int target,int idx,vector<vector<int>> &res,vector<int> &set){
+        if(!target){
+            res.push_back(set);
             return;
         }
+        if(idx == candidates.size())    return;
 
         if(target >= candidates[idx]){
-            combinationSum(candidates,target,idx + 1,res,set);
+            dfs(candidates,target,idx + 1,res,set);
             set.push_back(candidates[idx]);
-            combinationSum(candidates,target - candidates[idx],idx,res,set);
+            dfs(candidates,target - candidates[idx],idx,res,set);
             set.pop_back();
         }
     }
@@ -11663,25 +11662,25 @@ public:
 
         sort(candidates.begin(),candidates.end());
 
-        combinationSum2(candidates,target,res,set,0);
+        dfs(candidates,target,res,set,0);
 
         return res;
     }
 
 private:
-    void combinationSum2(vector<int> &candidates,int target,vector<vector<int>> &res,vector<int> &set,int idx){
+    void dfs(vector<int> &candidates,int target,vector<vector<int>> &res,vector<int> &set,int idx){
         if(target == 0){
             res.push_back(set);
             return;
         }
-        //cout << idx << endl;
+
         if(target >= candidates[idx]){
             set.push_back(candidates[idx]);
-            combinationSum2(candidates,target - candidates[idx],res,set,idx + 1);
+            dfs(candidates,target - candidates[idx],res,set,idx + 1);
             set.pop_back();
             while(idx < candidates.size() - 1 && candidates[idx + 1] == candidates[idx])    idx++;
             if(idx != candidates.size() - 1)
-                combinationSum2(candidates,target,res,set,idx + 1);
+                dfs(candidates,target,res,set,idx + 1);
         }
     }
 };
@@ -12037,15 +12036,11 @@ private:
 
             s.insert(nums[i]);
 
-            int tp = nums[i];
-            nums[i] = nums[idx];
-            nums[idx] = tp;
+            swap(nums[i],nums[idx]);
 
             permuteUnique(nums,idx + 1,res);
 
-            tp = nums[i];
-            nums[i] = nums[idx];
-            nums[idx] = tp;
+            swap(nums[i],nums[idx]);
         }
     }
 };