/**

* Author : WindAsMe

* File : canFinish.java

* Time : Create on 18-9-4

* Location : ../Home/JavaForLeeCode2/canFinish.java

* Function : LeetCode No.207

*/

public class canFinish {

// Foremost is to find the Graph has the circle.

private static boolean canFinishResult(int numCourses, int[][] prerequisites) {

// sustain the array

int[] inDegree = new int[numCourses];

// add all the input to array

for (int[] i : prerequisites)

inDegree[i[1]]++;

while (true) {

int index = -1;

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

if (inDegree[i] == 0) {

// Mark this index

inDegree[i] = -1;

index = i;

break;

}

}

if (index != -1) {

for (int[] prerequisite : prerequisites) {

if (prerequisite[0] == index)

inDegree[prerequisite[1]]--;

}

} else {

for (int i : inDegree) {

if (i != -1)

return false;

}

return true;

}

}

}

public static void main(String[] args) {

int[][] pre = {{0, 1}, {1, 0}};

System.out.println(canFinishResult(2, pre));

}

}