백준 14921번 용액 합성하기 C++

https://www.acmicpc.net/problem/14921

14921번: 용액 합성하기

 

투 포인터

 

#include <iostream>
#include <string>
#include <vector>
#include <math.h>
#include <algorithm>
#include <utility>
#include <stack>
#include <queue>
#include <math.h>
#include <set>
#include <map>
#include <list>
#include <unordered_map>
#include <unordered_set>
#include <iomanip>
#include <limits.h>

using namespace std;
using int64 = long long; 

int n;
vector<int> v;

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cout.tie(NULL);

    cin >> n;
    v = vector<int>(n);
    for (int i = 0; i < n; i++) {
        cin >> v[i];
    }
    int left = 0;
    int right = n - 1;
    int ans = INT_MAX;
    while (left < right) {
        int val = v[left] + v[right];
        if (val < 0) {
            left++;
        }
        else {
            right--;
        }
        if (abs(ans) > abs(val)) {
            ans = val;
        }
    }
    cout << ans;
}