1716. Calculate Money in Leetcode Bank

Easy

Hercy wants to save money for his first car. He puts money in the Leetcode bank every day.

He starts by putting in $1 on Monday, the first day. Every day from Tuesday to Sunday, he will put in $1 more than the day before. On every subsequent Monday, he will put in $1 more than the previous Monday.

Given n, return the total amount of money he will have in the Leetcode bank at the end of the nth day.

Example 1:

Input: n = 4
Output:
 10
Explanation:
 After the 4th day, the total is 1 + 2 + 3 + 4 = 10.

Example 2:

Input: n = 10
Output:
 37
Explanation:
 After the 10th day, the total is (1 + 2 + 3 + 4 + 5 + 6 + 7) + (2 + 3 + 4) = 37. Notice that on the 2nd Monday, Hercy only puts in $2.

Example 3:

Input: n = 20
Output:
 96
Explanation:
 After the 20th day, the total is (1 + 2 + 3 + 4 + 5 + 6 + 7) + (2 + 3 + 4 + 5 + 6 + 7 + 8) + (3 + 4 + 5 + 6 + 7 + 8) = 96.

Constraints:

• 1 <= n <= 1000

解題

Runtime: 0 ms, faster than 100.00%

Memory Usage: 1.9 MB, less than 14.29%

func totalMoney(n int) int {
    ans := 0
    
    allday := 1
    day := 1
    week := 0
    
    for allday <= n {
        if day > 7 { 
            day = 1 
            week++
        }
        
        ans += day + week
        day++
        allday++
    }
    
    return ans
}