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Format code with prettier (#3375)

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acbin
2022-10-03 17:23:00 +08:00
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parent 32b9b11ed5
commit e96f567bfc
464 changed files with 11483 additions and 6189 deletions
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97
src/main/java/com/thealgorithms/searches/BinarySearch2dArray.java
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@ -1,4 +1,5 @@
package com.thealgorithms.searches;
/*
To apply this method, the provided array must be strictly sorted. In this method, two pointers, one at 0th row
& the other at the last row are taken & the searching is done on the basis of the middle element of the middle column.
@ -6,69 +7,81 @@ If that element is equal to target, its coordinates are returned, else if it is
that element are ignored (because the elements above it will also be smaller than the target), else that element is
greater than the target, then the rows below it are ignored.
*/
public class BinarySearch2dArray
{
static int[] BinarySearch(int[][] arr, int target){
public class BinarySearch2dArray {
static int[] BinarySearch(int[][] arr, int target) {
int rowCount = arr.length, colCount = arr[0].length;
if (rowCount == 1){
if (rowCount == 1) {
return binarySearch(arr, target, 0, 0, colCount);
}
int startRow = 0, endRow = rowCount - 1, midCol = colCount/2;
int startRow = 0, endRow = rowCount - 1, midCol = colCount / 2;
while (startRow < endRow - 1){
while (startRow < endRow - 1) {
int midRow = startRow + (endRow - startRow) / 2; //getting the index of middle row
int midRow = startRow + (endRow - startRow) / 2; //getting the index of middle row
if (arr[midRow][midCol] == target){
return new int[] {midRow, midCol};
}
else if (arr[midRow][midCol] < target)
startRow = midRow;
else
endRow = midRow;
if (arr[midRow][midCol] == target) {
return new int[] { midRow, midCol };
} else if (arr[midRow][midCol] < target) startRow =
midRow; else endRow = midRow;
}
/*
/*
if the above search fails to find the target element, these conditions will be used to find the target
element, which further uses the binary search algorithm in the places which were left unexplored.
*/
if (arr[startRow][midCol] == target)
return new int[] {startRow, midCol};
if (arr[startRow][midCol] == target) return new int[] {
startRow,
midCol,
};
if (arr[endRow][midCol] == target)
return new int[] {endRow, midCol};
if (arr[endRow][midCol] == target) return new int[] { endRow, midCol };
if (target <= arr[startRow][midCol-1])
return binarySearch(arr, target, startRow, 0, midCol-1);
if (target <= arr[startRow][midCol - 1]) return binarySearch(
arr,
target,
startRow,
0,
midCol - 1
);
if (target >= arr[startRow][midCol+1] && target <= arr[startRow][colCount-1])
return binarySearch(arr,target, startRow, midCol+1, colCount-1);
if (
target >= arr[startRow][midCol + 1] &&
target <= arr[startRow][colCount - 1]
) return binarySearch(arr, target, startRow, midCol + 1, colCount - 1);
if (target <= arr[endRow][midCol-1])
return binarySearch(arr, target, endRow, 0, midCol-1);
else
return binarySearch(arr,target, endRow, midCol+1, colCount-1);
if (target <= arr[endRow][midCol - 1]) return binarySearch(
arr,
target,
endRow,
0,
midCol - 1
); else return binarySearch(
arr,
target,
endRow,
midCol + 1,
colCount - 1
);
}
static int[] binarySearch(int[][] arr, int target, int row, int colStart, int colEnd){
while (colStart <= colEnd){
static int[] binarySearch(
int[][] arr,
int target,
int row,
int colStart,
int colEnd
) {
while (colStart <= colEnd) {
int midIndex = colStart + (colEnd - colStart) / 2;
if (arr[row][midIndex] == target)
return new int[] {row, midIndex};
else if (arr[row][midIndex] < target)
colStart = midIndex + 1;
else
colEnd = midIndex - 1;
if (arr[row][midIndex] == target) return new int[] {
row,
midIndex,
}; else if (arr[row][midIndex] < target) colStart =
midIndex + 1; else colEnd = midIndex - 1;
}
return new int[] {-1, -1};
return new int[] { -1, -1 };
}
}