complete 32643.kt

storage/zeta/kt/completed/32643.kt

@@ -0,0 +1,53 @@
+class SequenceMaster(n: Int) {
+    val primes = mutableListOf<Int>()
+
+    init {
+        primes.add(2)
+        for (i in 3..n step 2) {
+            var flag = true
+            for (p in primes) {
+                if (p * p > i) {
+                    break
+                }
+                if (i % p == 0) {
+                    flag = false
+                    break
+                }
+            }
+            if (flag) {
+                primes.add(i)
+            }
+        }
+    }
+
+    fun request(a: Int, b: Int): Int {
+        val pa = primes.binarySearch(a)
+        val pb = primes.binarySearch(b)
+
+        return if (a == 1) {
+            1
+        } else {
+            0
+        } + if (pa >= 0 && pb >= 0) {
+            pb - pa + 1
+        } else if (pa < 0 && pb >= 0) {
+            pb - (-pa - 1) + 1
+        } else if (pa >= 0) {
+            (-pb - 1) - pa
+        } else {
+            (-pb - 1) - (-pa - 1)
+        }
+    }
+}
+
+fun main() = with(System.`in`.bufferedReader()) {
+    val (n, m) = this.readLine().split(' ').map { it.toInt() }
+    val seq = SequenceMaster(n)
+    System.out.bufferedWriter().use { bw ->
+        repeat(m) {
+            val (a, b) = this.readLine().split(' ').map { it.toInt() }
+            bw.write("${seq.request(a, b)}\n")
+        }
+    }
+
+}