稀疏数组
作者：互联网
public class sparseArray {
public static void main(String[] args) {
int[][] array = new int[11][11];
array[1][3] = 1;
array[2][4] = 2;
for (int[] i:array) {
for (int i1:i){
System.out.print(i1+"\t");
}
System.out.println();
}
//稀疏数组
System.out.println("=================================");
//计算非零数的个数
int sum = 0;
for (int i = 0; i < array.length; i++) {
for (int j = 0; j < array[i].length; j++) {
if (array[i][j] != 0){
sum++;
}
}
}
int[][] array1 = new int[sum+1][3];
array1[0][0] = 11;
array1[0][1] = 11;
array1[0][2] = sum;
//非零赋值
int count = 1;
for (int i = 0; i < array.length; i++) {
for (int j = 0; j < array[i].length; j++) {
if (array[i][j] != 0){
array1[count][0] = i; //把行的位置赋值
array1[count][1] = j; //把列的位置赋值
array1[count][2] = array[i][j]; //数值赋值
count++;
}
}
}
//打印输出
System.out.println("稀疏数组");
for (int i = 0; i < array1.length; i++) {
System.out.println(array1[i][0]+"\t"+
array1[i][1]+"\t"+array1[i][2]);
}
//稀疏数组还原
int[][] array2 = new int[array1[0][0]][array1[0][1]];
for (int i = 1; i < array1.length; i++) { //i要从1开始，不能从0，会下标越界，因为索引是从0到10，读取11会越界
array2[array1[i][0]][array1[i][1]] = array1[i][2];
}
for (int[] i:array2) {
for (int i1:i){
System.out.print(i1+"\t");
}
System.out.println();
}
}
}
输出结果：
0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 2 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 ================================= 稀疏数组 11 11 2 1 3 1 2 4 2 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 2 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
稀疏数组例子如图：
标签：int,array1,稀疏,System,++,数组,array,out 来源： https://www.cnblogs.com/hxisme/p/15754510.html