feat: kata/char-code-calculation (#799)

* docs: kata description

* feat: kata/char-code-calculation

---------

Co-authored-by: ParanoidUser <5120290+ParanoidUser@users.noreply.github.com>

Author: github-actions[bot]

kata/7-kyu/char-code-calculation/README.md

@@ -0,0 +1,26 @@
+# [Char Code Calculation](https://www.codewars.com/kata/char-code-calculation "https://www.codewars.com/kata/57f75cc397d62fc93d000059")
+
+Given a string, turn each character into its ASCII character code and join them together to create a number - let's call this number
+`total1`:
+
+```
+'ABC' --> 'A' = 65, 'B' = 66, 'C' = 67 --> 656667
+```
+
+Then replace any incidence of the number `7` with the number `1`, and call this number 'total2':
+
+```
+total1 = 656667
+ ^
+total2 = 656661
+ ^
+```
+
+Then return the difference between the sum of the digits in `total1` and `total2`:
+
+```
+ (6 + 5 + 6 + 6 + 6 + 7)
+- (6 + 5 + 6 + 6 + 6 + 1)
+-------------------------
+ 6
+```

kata/7-kyu/char-code-calculation/main/Kata.java

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+import static org.apache.commons.lang3.StringUtils.countMatches;
+
+interface Kata {
+  static int calc(String x) {
+    return 6 * x.chars().map(i -> countMatches(i + "", "7")).sum();
+  }
+}

kata/7-kyu/char-code-calculation/test/CharCodeCalculationTest.java

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+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.CsvSource;
+
+class CharCodeCalculationTest {
+  @ParameterizedTest
+  @CsvSource(textBlock = """
+      M, 12
+      jaam, 12
+      abcdef, 6
+      ifkhchlhfd, 6
+      aaaaaddddr, 30
+      jfmgklf8hglbe, 6
+      abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ, 96
+      """)
+  void sample(String s, int expected) {
+    assertEquals(expected, Kata.calc(s));
+  }
+}

kata/7-kyu/index.md

@@ -79,6 +79,7 @@
 - [Ch4113ng3](ch4113ng3 "59e9f404fc3c49ab24000112")
 - [Change two-dimensional array](change-two-dimensional-array "581214d54624a8232100005f")
 - [Changing letters](changing-letters "5831c204a31721e2ae000294")
+- [Char Code Calculation](char-code-calculation "57f75cc397d62fc93d000059")
 - [Character Counter](character-counter "56786a687e9a88d1cf00005d")
 - [Check contained matrix](check-contained-matrix "5a46179ce626c5ef8d000024")
 - [Check three and two](check-three-and-two "5a9e86705ee396d6be000091")