题目描述:
You have a total of n coins that you want to form in a staircase shape, where every k-th row must have exactly k coins.
Given n, find the total number of full staircase rows that can be formed.
n is a non-negative integer and fits within the range of a 32-bit signed integer.
Example 1:
n = 5
The coins can form the following rows:
¤
¤ ¤
¤ ¤
Because the 3rd row is incomplete, we return 2.
Example 2:
n = 8
The coins can form the following rows:
¤
¤ ¤
¤ ¤ ¤
¤ ¤
Because the 4th row is incomplete, we return 3.
把硬币按照第k行排列k个硬币放置,求在第几行排不满。
class Solution {
public:
int arrangeCoins(int n) {
int k=0;
while(true)
{
n-=k;
if(n<0) break;
k++;
}
return k-1;
}
};