문자열 치환 public String replaceString(String str, char oldChar, char newChar) { String result = new String(); for (char c : str.toCharArray()) { if (oldChar == c) { result += newChar; } else { result += c; } } return result; } 프로그래밍/알고리즘 2017.02.24
mergeSort public void mergeSort(int[] data, int p, int r) { int q = (p + r) / 2; if (p > r) { mergeSort(data, p, q); mergeSort(data, q + 1, r); merge(data, p, q, r); } } public void merge(int[] data, int p, int q, int r) { int i = p; int j = q + 1; int k = q; int[] temp = new int[data.length]; while (i 프로그래밍/알고리즘 2017.02.24
계산기(stack) public void testCalculator() { String[] tokens = new String[]{"2", "1", "+", "3", "*"}; //String[] tokens = new String[]{"4", "13", "5", "/", "+"}; calculator(tokens); } public void calculator(String[] data) { Stack stack = new Stack(); for (String str : data) { switch (str) { case "+": case "*": case "/": case "-": int a = Integer.parseInt(stack.pop()); int b = Integer.parseInt(stack.pop()); if.. 프로그래밍/알고리즘 2017.02.24