// 74. Search a 2D Matrix #include #include /* * 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 }