add 806

Author: fishercoder1534

Diff for: README.md

@@ -22,6 +22,7 @@ Your ideas/fixes/algorithms are more than welcome!
 
 |  #  |      Title     |   Solutions   | Time          | Space         | Video  | Difficulty  | Tag                   
 |-----|----------------|---------------|---------------|---------------|--------|-------------|-------------
+|806|[Number of Lines To Write String](https://leetcode.com/problems/number-of-lines-to-write-string/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_806.java) | O(n) | O(1) | |Easy|
 |799|[Champagne Tower](https://leetcode.com/problems/champagne-tower/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_799.java) | O(r^2) or O(1) | O(r^2) or O(1) | |Medium|
 |796|[Rotate String](https://leetcode.com/problems/rotate-string/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_796.java) | O(n) | O(1) | |Easy|
 |791|[Custom Sort String](https://leetcode.com/problems/custom-sort-string/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_791.java) | O(n+m) | O(1) | |Medium|

Diff for: src/main/java/com/fishercoder/solutions/_806.java

@@ -0,0 +1,62 @@
+package com.fishercoder.solutions;
+
+/**
+ * 806. Number of Lines To Write String
+
+ We are to write the letters of a given string S, from left to right into lines.
+ Each line has maximum width 100 units, and if writing a letter would cause the width of the line to exceed 100 units, it is written on the next line.
+ We are given an array widths, an array where widths[0] is the width of 'a', widths[1] is the width of 'b', ..., and widths[25] is the width of 'z'.
+
+ Now answer two questions:
+ how many lines have at least one character from S,
+ and what is the width used by the last such line?
+ Return your answer as an integer list of length 2.
+
+ Example :
+ Input:
+ widths = [10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10]
+ S = "abcdefghijklmnopqrstuvwxyz"
+ Output: [3, 60]
+ Explanation:
+ All letters have the same length of 10. To write all 26 letters,
+ we need two full lines and one line with 60 units.
+
+ Example :
+ Input:
+ widths = [4,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10]
+ S = "bbbcccdddaaa"
+ Output: [2, 4]
+ Explanation:
+ All letters except 'a' have the same length of 10, and
+ "bbbcccdddaa" will cover 9 * 10 + 2 * 4 = 98 units.
+ For the last 'a', it is written on the second line because
+ there is only 2 units left in the first line.
+ So the answer is 2 lines, plus 4 units in the second line.
+
+ Note:
+ The length of S will be in the range [1, 1000].
+ S will only contain lowercase letters.
+ widths is an array of length 26.
+ widths[i] will be in the range of [2, 10].
+
+ */
+public class _806 {
+  public static class Solution1 {
+    public int[] numberOfLines(int[] widths, String S) {
+      int numOfLines = 1;
+      int offsetInCurrentLine = 0;
+      for (char c : S.toCharArray()) {
+        if (offsetInCurrentLine + widths[c - 'a'] < 100) {
+          offsetInCurrentLine += widths[c - 'a'];
+        } else if (offsetInCurrentLine + widths[c - 'a'] == 100) {
+          numOfLines++;
+          offsetInCurrentLine = 0;
+        } else {
+          numOfLines++;
+          offsetInCurrentLine = widths[c - 'a'];
+        }
+      }
+      return new int[] {numOfLines, offsetInCurrentLine};
+    }
+  }
+}

Diff for: src/test/java/com/fishercoder/_806Test.java

@@ -0,0 +1,33 @@
+package com.fishercoder;
+
+import com.fishercoder.solutions._806;
+import org.junit.BeforeClass;
+import org.junit.Test;
+
+import static org.junit.Assert.assertArrayEquals;
+
+public class _806Test {
+  private static _806.Solution1 solution1;
+  private static int[] widths;
+
+  @BeforeClass
+  public static void setup() {
+    solution1 = new _806.Solution1();
+  }
+
+  @Test
+  public void test1() {
+    widths =
+        new int[] {10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10,
+            10, 10, 10, 10, 10, 10};
+    assertArrayEquals(new int[] {3, 60}, solution1.numberOfLines(widths, "abcdefghijklmnopqrstuvwxyz"));
+  }
+
+  @Test
+  public void test2() {
+    widths =
+        new int[] {4, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10,
+            10, 10, 10, 10, 10, 10};
+    assertArrayEquals(new int[] {2, 4}, solution1.numberOfLines(widths, "bbbcccdddaaa"));
+  }
+}