[6] Z 字形变换

src/leecode/6.z-字形变换.java

@@ -7,7 +7,46 @@ package leecode;/*
 // @lc code=start
 class Solution {
     public String convert(String s, int numRows) {
-        return null;
+        if (numRows == 0 || numRows == 1) return s;
+        int structNum = numRows + numRows - 2;
+        int wholeNum = s.length() / structNum;
+        int lastNum = s.length() % structNum;
+        int lastCell = lastNum / numRows + (lastNum / numRows == 0 ? 1 : lastNum % numRows);
+        int cellRight = wholeNum * (numRows - 1) + lastCell;
+        char[][] resultStruct = new char[numRows][cellRight];
+        int cursor = 1;
+        int structCount = 0;
+        int row = 0, cell = 0;
+        boolean back = false;
+        char[] chars = s.toCharArray();
+        for (char aChar : chars) {
+            if ((cursor - 1) / structNum > structCount) {
+                row = 0;
+                cell ++;
+                structCount = (cursor - 1) / structNum;
+                resultStruct[row][cell] = aChar;
+                row ++;
+                back = false;
+            } else if (row < numRows && !back) {
+                resultStruct[row][cell] = aChar;
+                row ++;
+            } else {
+                if (row == numRows) row --;
+                back = true;
+                cell ++;
+                row --;
+                resultStruct[row][cell] = aChar;
+            }
+            cursor ++;
+        }
+        StringBuilder sb = new StringBuilder();
+        for (char[] chars1 : resultStruct) {
+            for (char c : chars1) {
+                if (c == '\u0000') continue;
+                sb.append(c);
+            }
+        }
+        return sb.toString();
     }
 }
 // @lc code=end