complete 5597.cpp 15552.cpp 26156.kt

zeta_kotlin/completed/26156.kt

@@ -0,0 +1,40 @@
+import kotlin.math.*
+
+class NarockSolver(val s: String) {
+    companion object {
+        val HAXIM: Int = 1000000007
+    }
+    fun solve(): Int {
+        var cntR = 0
+        var cntO = 0
+        var cntC = 0
+        var cntS = 0
+        var rfront = 1
+        for (v: Char in s) {
+            if (v == 'R') {
+                cntR += rfront
+                cntR %= HAXIM
+            } else if (v == 'O') {
+                cntO += cntR
+                cntO %= HAXIM
+            } else if (v == 'C') {
+                cntC += cntO
+                cntC %= HAXIM
+            } else if (v == 'K') {
+                cntS += cntC
+                cntS %= HAXIM
+            }
+            rfront *= 2
+            rfront %= HAXIM
+        }
+
+        return cntS
+    }
+}
+
+fun main() {
+    readLine()
+    val s: String = readLine()!!
+    val solver = NarockSolver(s)
+    println(solver.solve())
+}