int main() { int n; int xfirst; int yfirst; bool h = true; bool v = true;

cin >> n;
vector<pair<int,int>> points(n);
cin.ignore(numeric_limits<streamsize>::max(), '\n');

for (int n_itr = 0; n_itr < n; n_itr++) 
{
    string xy_temp;
    getline(cin, xy_temp);
    vector<string> xy = split_string(xy_temp);    
    int x = stoi(xy[0]);
    int y = stoi(xy[1]);

    points[n_itr] = {x,y};
    xfirst = points[0].first;
}
    for (int i = 0; i < n;i++)
    {
        if (points[i].first != xfirst)
        {
            h = false;
            break;
        }
    }
    yfirst = points[0].second;
    for (int j = 0; j < n;j++)
    {
        if (points[j].second != yfirst)
        {
            dprintf(2,"%d <------ -------> %d\n",points[j].second,yfirst);
            v = false;
            break;
        }
    }
if (h || v)
    cout << "YES";
else
 cout << "NO";
return 0;

}

int main() { char* n_endptr; char* n_str = readline(); int n = strtol(n_str, &n_endptr, 10);

int xfirst;
int yfirst;
int h = true;
int v = true;
if (n_endptr == n_str || *n_endptr != '\0') { exit(EXIT_FAILURE); }
struct point *point_xy = malloc(sizeof(struct point) * n);
for (int n_itr = 0; n_itr < n; n_itr++) 
{
    char** xy = split_string(readline());
    char* x_endptr;
    char* x_str = xy[0];
    int x = strtol(x_str, &x_endptr, 10);
    if (x_endptr == x_str || *x_endptr != '\0') { exit(EXIT_FAILURE); }
    char* y_endptr;
    char* y_str = xy[1];
    int y = strtol(y_str, &y_endptr, 10);
    if (y_endptr == y_str || *y_endptr != '\0') { exit(EXIT_FAILURE); } 

    point_xy[n_itr].x = x;
    point_xy[n_itr].y = y;
}
xfirst = point_xy[0].x;
yfirst = point_xy[0].y;
//  dprintf(2,"%d <----xfirst----- -----yfirst------>%d\n",xfirst,yfirst);
 for (int i = 0; i < n;i++)
 {
    //  dprintf(2,"%d <----xfirst----- -----yfirst------>%d\n",xfirst,yfirst);
    // dprintf(2,"%d <----xfirst----- -----points------>%d\n",xfirst,point_xy[i].x);
    if (point_xy[i].x != xfirst)
    {
        h = false;
        break;
    }
 }
 for (int j = 0; j < n;j++)
 {

    if (point_xy[j].y != yfirst)
    {
        v = false;
        break;
    }

 }
if (h || v)
    printf("YES");
else 
    printf("NO");
return 0;

}

!/bin/python3

import math import os import random import re import sys

if name == 'main': n = int(input()) H = [] V = []

for n_itr in range(n):
    xy = input().split()

    x = int(xy[0])

    y = int(xy[1])

    H.append(xy[0])
    V.append(xy[1])
setH = set(H)
setV = set(V)
if len(setH) == 1 or len(setV) == 1:
    print("YES")
else:
    print("NO")

My javascript solution (two liner, could easily be one):

function main() {
    const points = Array(+readLine()).fill().map(_ => readLine().split(' ').map(x => +x));
    console.log([0, 1].some(x => points.every((y, _, arr) => y[x] == arr[0][x])) ? 'YES' : 'NO');
}

int main() { int n,x,y,x1,y1,cx=0,cy=0,flag=0,num; scanf("%d",&n); num=n; while(n--) { if(flag==0) { scanf("%d%d",&x,&y); x1=x; y1=y; flag=1; } else if(flag==1) { scanf("%d%d",&x,&y); if(x==x1) { cx++; } else if(y==y1) { cy++; } } } if(cx==num-1 || cy==num-1) { printf("YES"); } else { printf("NO"); } }