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sort-colors.cpp
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sort-colors.cpp
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// Given an array with n objects colored red, white or blue, sort them in-place so that objects of the same color are adjacent, with the colors in the order red, white and blue.
//
// Here, we will use the integers 0, 1, and 2 to represent the color red, white, and blue respectively.
//
// Note: You are not suppose to use the library's sort function for this problem.
//
// Example:
//
//
// Input: [2,0,2,1,1,0]
// Output: [0,0,1,1,2,2]
//
// Follow up:
//
//
// A rather straight forward solution is a two-pass algorithm using counting sort.
// First, iterate the array counting number of 0's, 1's, and 2's, then overwrite array with total number of 0's, then 1's and followed by 2's.
// Could you come up with a one-pass algorithm using only constant space?
//
//
class Solution {
public:
void sortColors(vector<int>& nums) {
int len = nums.size() - 1;
for (int i = 0; i <= len; i++) {
if (nums[i] < 1) {
int temp = nums[i];
nums.erase(nums.begin() + i);
nums.insert(nums.begin(), temp);
}
else if (nums[i] > 1) {
int temp = nums[i];
nums.erase(nums.begin() + i);
nums.push_back(temp);
//how to quit for loop
i -= 1;
len -= 1;
}
}
}
};