【LeetCode & 剑指offer 刷题笔记】目录（持续更新中...）
228. Summary Ranges
Given a sorted integer array without duplicates, return the summary of its ranges.
Example 1:
Input:
[0,1,2,4,5,7]
Output:
["0->2","4->5","7"]
Explanation:
0,1,2 form a continuous range; 4,5 form a continuous range.
Example 2:
Input:
[0,2,3,4,6,8,9]
Output:
["0","2->4","6","8->9"]
Explanation:
2,3,4 form a continuous range; 8,9 form a continuous range.
/*
问题：有序数组总结范围（无重复数）
方法：扫描数组，用双指针找范围的左右端点
*/
class
Solution
{
public
:
vector
<
string
>
summaryRanges
(
vector
<
int
>&
nums
)
{
vector
<
string
>
res
;
if
(
nums
.
empty
())
return
res
;
for
(
int
i
=
0
;
i
<
nums
.
size
();)
{
int
left
=
i
; //i=0~n-1
int
right
=
i
;
while
(
right
+
1
<
nums
.
size
()
&&
nums
[
right
+
1
]
==
nums
[
right
]
+
1
)
right
++;
if
(
right
==
left
)
//
范围等于
1
时
res
.
push_back
(
to_string
(
nums
[
right
]));
else
//
范围大于
1
时
res
.
push_back
(
to_string
(
nums
[
left
])
+
"->"
+
to_string
(
nums
[
right
]));
i
=
right
+
1
;
//
移动到当前范围的后一个元素
}
return
res
;
}
};