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// 74. Search a 2D Matrix
#include <stdbool.h>
#include <stdio.h>
/*
* given an 'm x n' integer matrix 'matrxi' with the following two properties:
* - each row is sorted in non-decreasing order.
* - the first integer of each row is greater than the last integer of the
* previous row. given an integer 'target', return true if 'target' is in
* 'matrix', or false otherwise. you must write a solution in 'O(log(m * n))'
* time complexity
*/
bool searchMatrix(int **matrix, int matrix_size, int *matrix_col_size,
int target) {
int i = 0, j = *matrix_col_size * matrix_size - 1;
while (i <= j) {
int mid = (i + j) / 2;
int row = mid / *matrix_col_size;
int col = mid % *matrix_col_size;
if (matrix[row][col] < target)
i = mid + 1;
else if (matrix[row][col] > target)
j = mid - 1;
else
return true;
}
return false;
}
int main() {
int matrix[3][4] = {{1, 3, 5, 7}, {10, 11, 16, 20}, {23, 30, 34, 60}};
printf("%d\n", searchMatrix(matrix, 4, NULL, 3)); // expect: 1
printf("%d\n", searchMatrix(matrix, 4, NULL, 13)); // expect: 0
}
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