Create Han_Xin_Counting_Soldiers.c (#91)

* Create Han_Xin_Counting_Soldiers.c

Add a example of Han Xin Counting Soldiers.

* test Chinese remainder theorem

Co-authored-by: shellhub <[email protected]>

Author: ReganYue

basics/chinese_remainder_theorem.c

@@ -0,0 +1,24 @@
+/**
+ * https://en.wikipedia.org/wiki/Chinese_remainder_theorem
+ */
+#include <assert.h>
+
+int getSoldiers(int limit) {
+    for (int i = limit; i >= 0; --i) {
+        if (i % 3 == 2 && i % 5 == 3 && i % 7 == 2) {
+            return i;
+        }
+    }
+    return -1; // unreachable code
+}
+
+void test() {
+    assert(getSoldiers(100) == 23);
+    assert(getSoldiers(1000) == 968);
+    assert(getSoldiers(10000) == 9998);
+}
+
+int main() {
+    test();
+    return 0;
+}