[leet] 로마숫자 바꾸기 (mid)

Author: hyeonbinHur

허현빈/7주차/260213-1.js

@@ -0,0 +1,55 @@
+/**
+ * @param {string} s
+ * @return {number}
+ */
+var romanToInt = function(s) {
+    const val = {
+        "I":1,
+        "V":5,
+        "X":10,
+        "L":50,
+        "C":100,
+        "D":500,
+        "M":1000,
+    }
+
+    let ans = 0;
+    for(let i = 0; i < s.length ; i ++){
+        if(s[i] === "I"){
+            if(s[i+1] === "V"){
+                ans += 4
+                i++
+                continue
+            }else if(s[i+1] === "X"){
+                ans += 9
+                i++
+                continue
+            }
+        }else if(s[i] === "X"){
+                if(s[i+1] === "L"){
+                    ans+= 40
+                    i++
+                    continue
+
+                }else if(s[i+1] === "C"){
+                    ans+= 90
+                    i++
+                    continue
+                }
+
+        }else if(s[i] === "C"){
+            if(s[i+1] === "D"){
+                ans+=400
+                i++
+                continue
+            }else if(s[i+1] ==="M"){
+                ans += 900
+                i++
+                continue
+            }
+        }
+
+         ans += val[s[i]]
+    }
+    return ans
+};

허현빈/7주차/260214-2.js

@@ -0,0 +1,40 @@
+/**
+ * @param {number} num
+ * @return {string}
+ */
+var intToRoman = function(n1) {
+    const numStr = n1.toString();
+    const len = numStr.length;
+    
+    const map = new Map([
+        [1, "I"], [5, "V"], [10, "X"], 
+        [50, "L"], [100, "C"], [500, "D"], [1000, "M"]
+    ]);
+
+    let ans = "";
+
+    for (let i = 0; i < len; i++) {
+        const val = parseInt(numStr[i]); 
+        const power = Math.pow(10, len - 1 - i); 
+
+        const one = map.get(power);          
+        const five = map.get(power * 5);      
+        const ten = map.get(power * 10);     
+
+        if (val === 9) {
+            ans += one + ten;
+        } else if (val >= 5) {
+            ans += five;
+            for (let j = 0; j < val - 5; j++) {
+                ans += one;
+            }
+        } else if (val === 4) {
+            ans += one + five;
+        } else {
+            for (let j = 0; j < val; j++) {
+                ans += one;
+            }
+        }
+    }
+    return ans;
+};