https://leetcode.com/problems/calculate-money-in-leetcode-bank/description/
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
- code
class Solution {
public int totalMoney(int n) {
int week = n / 7 + 1;
int dayInWeek = n % 7;
int res = 0;
int start = week;
while (dayInWeek > 0){
res += start;
start++;
dayInWeek--;
}
for (int i = 1; i < week; i++){
res += 1 + 2 + 3 + 4 + 5 + 6 + 7 + (i-1) * 7;
}
return res;
}
}