矩阵
package top100.top矩阵;
import java.util.ArrayList;
import java.util.List;
public class TOP {
public void setZeroes(int[][] matrix) {
int m = matrix.length;
int n = matrix[0].length;
boolean[] row = new boolean[m];
boolean[] col = new boolean[n];
for (int i = 0; i < m; i++) {
for (int j = 0; j < n; j++) {
if (matrix[i][j] == 0) {
row[i] = col[j] = true;
}
}
}
for (int i = 0; i < m; i++) {
for (int j = 0; j < n; j++) {
if (row[i] || col[j]) {
matrix[i][j] = 0;
}
}
}
}
public List<Integer> spiralOrder(int[][] matrix) {
List<Integer> res = new ArrayList<>();
int m = matrix.length, n = matrix[0].length;
int top = 0, bottom = m - 1, left = 0, right = n - 1;
int count = m * n;
while (count > 0) {
for (int i = left; i <= right && count > 0; i++) {
res.add(matrix[top][i]);
count--;
}
top++;
for (int i = top; i <= bottom && count > 0; i++) {
res.add(matrix[i][right]);
count--;
}
right--;
for (int i = right; i >= left && count > 0; i--) {
res.add(matrix[bottom][i]);
count--;
}
bottom--;
for (int i = bottom; i >= top && count > 0; i--) {
res.add(matrix[i][left]);
count--;
}
left++;
}
return res;
}
public void rotate(int[][] matrix) {
int n = matrix.length;
for (int i = 0; i < n / 2; i++) {
for (int j = 0; j < n; j++) {
int v = matrix[n - i - 1][j];
matrix[n - i - 1][j] = matrix[i][j];
matrix[i][j] = v;
}
}
for (int i = 0; i < n; i++) {
for (int j = i + 1; j < n; j++) {
int v = matrix[i][j];
matrix[i][j] = matrix[j][i];
matrix[j][i] = v;
}
}
}
public boolean searchMatrix(int[][] matrix, int target) {
int m = matrix.length, n = matrix[0].length;
int i = m - 1, j = 0;
while (i >= 0 && j < n) {
if (matrix[i][j] > target) {
i--;
} else if (matrix[i][j] < target) {
j++;
} else {
return true;
}
}
return false;
}
}