LC 599. Minimum Index Sum of Two Lists

Title Description

Suppose Andy and Doris want to choose a restaurant for dinner, and they both have a list of favorite restaurants represented by strings.

You need to help them find out their common interest with the least list index sum. If there is a choice tie between answers, output all of them with no order requirement. You could assume there always exists an answer.

Example 1:

Input:
["Shogun", "Tapioca Express", "Burger King", "KFC"]
["Piatti", "The Grill at Torrey Pines", "Hungry Hunter Steakhouse", "Shogun"]
Output: ["Shogun"]
Explanation: The only restaurant they both like is "Shogun".

Example 2:

Input:
["Shogun", "Tapioca Express", "Burger King", "KFC"]
["KFC", "Shogun", "Burger King"]
Output: ["Shogun"]
Explanation: The restaurant they both like and have the least index sum is "Shogun" with index sum 1 (0+1).

Answers

 1 class Solution {
 2 public:
 3     vector<string> findRestaurant(vector<string>& list1, vector<string>& list2) {
 4         
 5         vector<string>  res;
 6         unordered_map<string, int> map;
 7         for(size_t i = 0 ; i< list1.size(); i++) 
 8             map[list1[i]] = i ; // list1 = key ; i = value ;
 9         
10         size_t  min =INT_MAX;
 . 11          
12 is          for (size_t I = 0 ; I <list2.size (); I ++ ) {
 13 is              Auto ITER = map.find (List2 [I]);
 14              IF (! = ITER map.end ()) {
 15                  IF (iter-> sECOND + I < min) {
 16                      min = Map [List2 [I]] + I;
 . 17                      res.assign ( . 1 , List2 [I]); // directly to assign a value to a first , clear and does not need to be reassigned 
18 is                      
. 19                  } the else  IF (iter-> SECOND == + I min) {
 20 is                     res.push_back(list2[i]);
21                 }
22                 
23             }
24         }
25         return res;
26     }
27 };

Analysis Remarks

1. for loop, int size_t be replaced accelerated.

2. vector.assign (1, value) + assignment to clear or two steps.

3. iter -> first and iter -> second faster.