Summary Ranges

Given a sorted integer array without duplicates, return the summary of its ranges.

For example, given

[0,1,2,4,5,7]

, return

["0->2","4->5","7"].

class Solution {
public:
vector<string> summaryRanges(vector<int>& nums) {
vector<string> result;
int n = nums.size();
if (n < 1)
{
return result;
}

int left = 0;
int right = 0;
char temp[100];
for (int i = 1; i < n; i++)
{
if (nums[i] == nums[right]+1)
{
right = i;
}
else
{
sprintf(temp, "%d", nums[left]);
string str(temp);
if (left != right)
{
sprintf(temp, "%d", nums[right]);
str += "->" + string(temp);
}
result.push_back(str);
left = right = i;
}
}
sprintf(temp, "%d", nums[left]);
string str(temp);
if (left != right)
{
sprintf(temp, "%d", nums[right]);
str += "->" + string(temp);
}
result.push_back(str);

return result;
}
};