Merge pull request #54 from ShinchanTheMaster/master

Create Paint-House- III.cpp

Leetcode/Paint-House- III.cpp

@@ -0,0 +1,81 @@
+class Solution {
+    int dp[101][20][101];
+    const int maxi = 1e7;
+
+    void find_min(int i, int k, int n, int tmp[]){     
+        for(int j = 0; j < n; ++j){
+            if(tmp[0] > dp[i][j][k] and dp[i][j][k] != -1){
+                tmp[1] = tmp[0];
+                tmp[0] = dp[i][j][k];
+            }
+            else if(tmp[0] <= dp[i][j][k] and tmp[1] > dp[i][j][k])
+                tmp[1] = dp[i][j][k];
+        }
+
+        if(tmp[0] == maxi){
+            tmp[0] = -1;
+            tmp[1] = -1;
+        }
+        else if(tmp[1] >= maxi)
+            tmp[1] = -1;
+    }
+
+public:
+    int minCost(vector<int>& houses, vector<vector<int>>& cost, int m, int n, int target) {
+        memset(dp, -1, sizeof(dp));
+        int prev[] = {maxi, maxi + 1};
+        int idx = 0;
+
+        if(houses[0] == 0)
+            for(int j = 0; j < n; ++j)
+                dp[1][j][1] = cost[0][j]; 
+        else
+            dp[1][houses[0] - 1][1] = 0;
+
+        for(int i = 2; i < m + 1; ++i){
+            for(int k = 1; k <= i and k < target + 1; ++k){
+                find_min(i - 1, k - 1, n, prev);
+
+                if(houses[i - 1] == 0){
+                    for(int j = 0; j < n; ++j){                        
+                        if(prev[0] == dp[i - 1][j][k - 1])
+                            idx = 1;
+                        else
+                            idx = 0;
+
+                        if(prev[idx] != -1 and dp[i - 1][j][k] != -1 and (i + (target - k) <= m))
+                            dp[i][j][k] = min(dp[i - 1][j][k], prev[idx]) + cost[i - 1][j];
+                        else if(prev[idx] != -1)
+                            dp[i][j][k] = prev[idx] + cost[i - 1][j];
+                        else if(dp[i - 1][j][k] != -1 and (i + (target - k) <= m))
+                            dp[i][j][k] = dp[i - 1][j][k] + cost[i - 1][j];
+                        else
+                            dp[i][j][k] = -1;
+                    }
+                }
+                else{
+                    if(prev[0] == dp[i - 1][houses[i - 1] - 1][k - 1])
+                        idx = 1;
+                    else
+                        idx = 0;
+
+                    if(prev[idx] != -1 and dp[i - 1][houses[i - 1] - 1][k] != -1 and (i + (target - k) <= m))
+                        dp[i][houses[i - 1] - 1][k] = min(dp[i - 1][houses[i - 1] - 1][k], prev[idx]);
+                    else if(prev[idx] != -1)
+                        dp[i][houses[i - 1] - 1][k] = prev[idx];
+                    else if(dp[i - 1][houses[i - 1] - 1][k] != -1 and (i + (target - k) <= m))
+                        dp[i][houses[i - 1] - 1][k] = dp[i - 1][houses[i - 1] - 1][k];
+                    else
+                        dp[i][houses[i - 1] - 1][k] = -1;               
+                }
+
+                prev[0] = maxi;
+                prev[1] = maxi + 1;
+            }
+        }
+
+        find_min(m, target, n, prev);
+
+        return prev[0];
+    }
+};