add PROGRAMMERS-12913

Author: codejsha

README.md

@@ -7,6 +7,7 @@
 | PROGRAMMERS-1844 |[python](programmers/problem1844)|[게임 맵 최단거리 (The Shortest Distance on Game Map)](https://school.programmers.co.kr/learn/courses/30/lessons/1844)|
 | PROGRAMMERS-12909 :star:|[java](programmers/problem12909)|[올바른 괄호 (A Correct Parentheses)](https://school.programmers.co.kr/learn/courses/30/lessons/12909)|
 | PROGRAMMERS-12911 |[java](programmers/problem12911)|[다음 큰 숫자 (Next Big Number)](https://school.programmers.co.kr/learn/courses/30/lessons/12911)|
+| PROGRAMMERS-12913 |[java](programmers/problem12913)|[땅따먹기 (Hopscotch)](https://school.programmers.co.kr/learn/courses/30/lessons/12913)|
 | PROGRAMMERS-12914 |[java](programmers/problem12914)|[멀리 뛰기 (Long Jump)](https://school.programmers.co.kr/learn/courses/30/lessons/12914)|
 | PROGRAMMERS-12924 :star:|[java](programmers/problem12924)|[숫자의 표현 (Number Expressions)](https://school.programmers.co.kr/learn/courses/30/lessons/12924)|
 | PROGRAMMERS-12927 |[java](programmers/problem12927)|[야근 지수 (Overtime Index)](https://school.programmers.co.kr/learn/courses/30/lessons/12927)|

programmers/problem12913/Hopscotch_DFS.java

@@ -0,0 +1,36 @@
+packageproblem12913;
+
+/**
+ * DFS solution
+ * this solution is not accepted because of time limit exceeded
+ */
+publicclassHopscotch_DFS{
+publicstaticvoidmain(String[] args){
+finalvarsol = newHopscotch_DFS();
+finalvarland = newint[][]{{1, 2, 3, 5},{5, 6, 7, 8},{4, 3, 2, 1}};
+finalvarexpected = 16;
+finalvarresult = sol.solution(land);
+System.out.println("expected: " + expected + " result: " + result);
+ }
+
+publicintsolution(int[][] land){
+varmax = 0;
+for (vari = 0; i < land[0].length; i++){
+max = Math.max(max, dfs(land, 0, i, 0));
+ }
+returnmax;
+ }
+
+privateintdfs(int[][] land, introw, intcol, intsum){
+if (row == land.length){
+returnsum;
+ }
+varmax = 0;
+for (vari = 0; i < land[row].length; i++){
+if (i != col){
+max = Math.max(max, dfs(land, row + 1, i, sum + land[row][i]));
+ }
+ }
+returnmax;
+ }
+}

programmers/problem12913/Hopscotch_DP.java

@@ -0,0 +1,39 @@
+packageproblem12913;
+
+importjava.util.Arrays;
+
+/**
+ * DP solution
+ */
+publicclassHopscotch_DP{
+publicstaticvoidmain(String[] args){
+finalvarsol = newHopscotch_DP();
+finalvarland = newint[][]{{1, 2, 3, 5},{5, 6, 7, 8},{4, 3, 2, 1}};
+finalvarexpected = 16;
+finalvarresult = sol.solution(land);
+System.out.println("expected: " + expected + " result: " + result);
+ }
+
+publicintsolution(int[][] land){
+finalvardp = newint[land.length][land[0].length];
+// copy first row
+System.arraycopy(land[0], 0, dp[0], 0, land[0].length);
+
+// i = row, j and k = col
+for (vari = 1; i < land.length; i++){
+for (varj = 0; j < land[i].length; j++){
+for (vark = 0; k < land[i].length; k++){
+if (j != k){
+dp[i][j] = Math.max(dp[i][j], dp[i - 1][k] + land[i][j]);
+ }
+ }
+ }
+ }
+
+varmax = 0;
+for (vari = 0; i < land[0].length; i++){
+max = Math.max(max, dp[land.length - 1][i]);
+ }
+returnmax;
+ }
+}