[BOJ] 28324 스케이트 연습 (S4)

Author: abcxj123

정건우/2주차/260107.java

@@ -0,0 +1,36 @@
+//https://www.acmicpc.net/problem/28324
+
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.util.StringTokenizer;
+
+public class BOJ_S4_28324_스케이트연습 {
+
+    public static void main(String[] args) throws IOException {
+        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+
+        int N = Integer.parseInt(br.readLine());
+        int [] nums = new int[N];
+
+        StringTokenizer st = new StringTokenizer(br.readLine());
+        for (int i = 0; i < N; i++) {
+            nums[i] = Integer.parseInt(st.nextToken());
+        }
+
+        long ans = 0;
+        int expectNum = 1;
+
+        for (int i = N-1; i >= 0; i--) {
+            if(nums[i] >= expectNum) {
+                ans += expectNum++;
+            } else {
+                ans += nums[i];
+                expectNum = nums[i]+1;
+            }
+        }
+
+        System.out.println(ans);
+
+    }
+}