1080-done

sowon-dev · sowon-dev · commit e7def51058ac · 2021-01-31T12:20:13.000+09:00
diff --git a/src/codeup100/c1080.java b/src/codeup100/c1080.java
@@ -1,29 +1,53 @@
 package codeup100;
 
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStreamReader;
 import java.util.Scanner;
 
 public class c1080 {
-    public static void main(String[] args) {
+    public static void main(String[] args) throws IOException {
+        //sol1 Memory 14952 Runtime 113
+        /*
         Scanner sc = new Scanner(System.in);
         int num = sc.nextInt();
         sc.close();
 
         int sum = 0;
         int i;
-
-        //&#45236;&#53076;&#46300;
-/*
         for(i = 1; sum < num; i++){
             sum += i;
         }
         System.out.println(i-1);
-*/
+        */
 
-        //&#46160;&#48264;&#51704;&#53076;&#46300;
-        for(i=1; i<num; i++){
-            sum += i;
-            if (sum >= num ) break;
+        //sol2
+        // Using sc.close()  :  Memory 14348 Runtime 114
+        // Not using sc.close() : Memory 14312 Runtime 112
+        /*
+        Scanner sc = new Scanner(System.in);
+        int sum = sc.nextInt();
+        sc.close();
+
+        int tempSum = 0;
+        int i = 0;
+        for(i=0;  tempSum < sum; i++){
+          tempSum += i;
+          if(tempSum >= sum) break;
         }
         System.out.println(i);
+        */
+
+        //sol3 : use BufferReader
+        //Memory 11128 Runtime 66
+        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+        int sum = Integer.parseInt(br.readLine());
+        int tempSum = 0;
+        int j = 0;
+        for(j=0;  tempSum < sum; j++){
+            tempSum += j;
+            if(tempSum >= sum) break;
+        }
+        System.out.println(j);
     }
 }
