Lock on!

#include<stdio.h>
int min(int a,int b){
    return (a < b ? a : b);
}
int abs(int a){
    return (a < 0 ? a * -1 : a);
}

int arr[1000010];
int main()
{
    int n,p;
    scanf("%d %d",&n,&p);
    //for(int i=0;i<1000010;i++)arr[i] = 0;
    for(int i=0;i<n;i++){
        int l,r;
        scanf("%d %d",&l,&r);
        if(l > r){
            int temp = l;
            l = r;
            r = temp;
        }
        l++;
        r++;
        arr[l]++;
        arr[r+1]--;
    }
    p++;
    int ans = 2e9;
    for(int i = 1 ; i <= 1000005 ; i++){
        arr[i] = arr[i-1] + arr[i];
        if(arr[i] == n){
            ans = min(ans,abs(p - i));
        }
    }
    printf("%d",(ans == 2e9 ? -1 : ans));
    return 0;
}