\n In this article, we will cover a famous problem called “I Will Become the Resident Association President” through an algorithm problem-solving course using Python.
\n This problem requires a solution using dynamic programming based on the given conditions.
\n We will define the problem, demonstrate the method through examples, and finally write the code to solve the problem.\n<\/p>\n
\nProblem:<\/strong> \n For example, if we want to know the number of residents in apartment 4 on the 3rd floor, we need to add the number of residents from apartment 1 to apartment 4 on the 3rd floor. \nInput:<\/strong> \nOutput:<\/strong> \n To solve this problem, we can use a dynamic programming approach. \n The number of residents on the 1st floor is always the same for each apartment number, so we initialize the table based on this.\n<\/p>\n \n The number of residents in apartment B on each floor can be expressed as the sum of the number of residents from all apartments on the previous floor. \n Using the above recurrence relation, we calculate the values for A-th floor and apartment B through a loop. \n Through this problem, we explored the application of dynamic programming. We could understand how important it is to analyze the problem and design an algorithm to solve the given problem. \n More practice is needed to solve problems effectively. I hope you can develop an algorithmic mindset by solving a variety of problems.\n<\/p>\n \n Wishing you a successful coding test!<\/p>\n","protected":false},"excerpt":{"rendered":"
\n The resident association president is a resident living in apartment number B on the A-th floor, among N residents.
\n The apartment has K floors, and each floor has apartments numbered from 1 to K.
\n The problem is to calculate the total number of residents living in apartment B on the A-th floor.
\n The number of residents living in apartment B on the A-th floor varies depending on the apartment number on each floor, and the rule is as follows:\n<\/p>\n\n
\n The problem is to find the number of residents in apartment B on the A-th floor for the given A and B.\n<\/p>\nInput and Output Format<\/h3>\n
\n The first line contains the number of test cases T.
\n Following this, A and B will be given for each test case over T lines.\n<\/p>\n
\n For each test case, print the number of residents in apartment B on the A-th floor.\n<\/p>\nExample<\/h3>\n
\nInput Example:<\/strong>\n2\n1 3\n2 3\n\nOutput Example:<\/strong>\n3\n6\n<\/pre>\n
Problem-Solving Approach<\/h3>\n
\n We can create a two-dimensional table to store the number of residents for each apartment number on each floor to solve the problem.\n<\/p>\nStep 1: Table Initialization<\/h4>\n
Step 2: Set Dynamic Programming Relation<\/h4>\n
\n Therefore, the recurrence relation is as follows:<\/p>\n\n dp[A][B] = dp[A-1][1] + dp[A-1][2] + ... + dp[A-1][B]\n<\/pre>\n
Step 3: Repetitive Process<\/h4>\n
\n This way, we will eventually obtain the number of residents in apartment B on the A-th floor.\n<\/p>\nCode Solution<\/h3>\n
\n
\ndef calculate_people(A, B):\n # Function to calculate the number of residents in apartment B on the A-th floor\n dp = [[0] * (B + 1) for _ in range(A + 1)]\n \n # Initialize the 1st floor\n for j in range(1, B + 1):\n dp[1][j] = j\n \n # Calculate number of residents using dynamic programming\n for i in range(2, A + 1): # A-th floor\n for j in range(1, B + 1): # B-th apartment\n dp[i][j] = sum(dp[i-1][k] for k in range(1, j + 1))\n \n return dp[A][B]\n\n# Processing test cases\nT = int(input())\nfor _ in range(T):\n A, B = map(int, input().split())\n print(calculate_people(A, B))\n<\/code>\n<\/pre>\nConclusion<\/h3>\n
\n This approach can also help in finding more efficient solutions when solving other coding test problems.\n<\/p>\n