package leetcode;

import com.sun.scenario.effect.Offset;

/**

* Created by solie_h on 2018/11/16.

*/

public class NumDeletekMaximum {

public static String removeKDigits(String num, int k) {

int resultLength = num.length() - k;

char[] stack = new char[num.length()];

int top = 0;

for (int i = 0; i < num.length(); i++) {

char c = num.charAt(i);

while (top > 0 && stack[top - 1] > c && k > 0) {

top = top - 1;

k = k - 1;

}

stack[top++] = c;

}

int offset = 0;

while (offset < resultLength && stack[offset] == '0') {

offset++;

}

return offset == resultLength ? "0" : new String(stack, offset, resultLength - offset);

}

public static void main(String[] args) {

System.out.println(removeKDigits("17287", 2));

}

}