Merge branch 'main' of https://github.com/oliveyoung-algorithm/algorithm

Author: uiop5809

정건우/2주차/260106.java

@@ -0,0 +1,55 @@
+//https://www.acmicpc.net/problem/1935
+
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.util.Stack;
+
+public class BOJ_S3_1935_후위표기식2 {
+    public static void main(String[] args) throws IOException {
+        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+
+        int N = Integer.parseInt(br.readLine());
+        Stack<Double> stack = new Stack<>();
+        double [] nums = new double[N];
+
+        String s = br.readLine();
+
+        for(int i = 0; i < N; i++) {
+            nums[i] = Integer.parseInt(br.readLine());
+        }
+
+        for (int i = 0; i < s.length(); i++) {
+            char c = s.charAt(i);
+
+            switch(c) {
+                case '+':
+                    double a1 = stack.pop();
+                    double a2 = stack.pop();
+                    stack.push(a1 + a2);
+                    break;
+                case '-':
+                    double b1 = stack.pop();
+                    double b2 = stack.pop();
+                    stack.push(b2 - b1);
+                    break;
+                case '*':
+                    double c1 = stack.pop();
+                    double c2 = stack.pop();
+                    stack.push(c1 * c2);
+                    break;
+                case '/':
+                    double d1 = stack.pop();
+                    double d2 = stack.pop();
+                    stack.push(d2 / d1);
+                    break;
+                default:
+                    stack.push(nums[c-'A']);
+                    break;
+            }
+        }
+
+        System.out.printf("%.2f", stack.pop());
+
+    }
+}