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printmatrixspiralorder

admin 1月 14, 2021 0

输入一个矩阵，按照从外向里以顺时针的顺序依次打印出每一个数字，例如，如果输入如下4 X 4矩阵： 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 则依次打印出数字1,2,3,4,8,12,16,15,14,13,9,5,6,7,11,10.

import java.util.ArrayList;
public class Solution {

public ArrayList<Integer> printMatrix(int [][] matrix) {
    int tR = 0;
    int tC = 0;
    int dR = matrix.length - 1;
    int dC = matrix[0].length - 1;
    ArrayList<Integer> list = new ArrayList<Integer>();
    while(tR <= dR && tC <= dC){
         if(tR == dR){
             for(int i = tC; i<= dC; i++){
                 list.add( matrix[tR][i]);
             }
         }else if(tC == dC){
             for(int i = tR; i<= dR; i++){
                  list.add( matrix[i][tC]);
             }
         }else{
             int curC = tC;
             int curR = tR;
             while (curC != dC){
                  list.add( matrix[tR][curC]);
                 curC++;
             }
             while (curR != dR) {
                 list.add( matrix[curR][dC]);
                curR++;
            }
             while (curC != tC) {
                 list.add( matrix[dR][curC]);
                curC--;
            }
             while (curR != tR) {
                 list.add( matrix[curR][tC]);
                curR--;
            }
         }
            tR++;
            dR--; 
            tC++;            
            dC--;
        }
    return list;
}

}