ural 1203. Scientific Conference

http://acm.timus.ru/problem.aspx?space=1&num=1203

#include <cstdio>#include <cstring>#include <algorithm>#define maxn 400000using namespace std;struct node{    int s,e;    bool operator <(const node &a)const    {        return ((e<a.e)||(e==a.e&&s>a.s));    }}p[maxn];int dp[maxn];int main(){    int n;    scanf("%d",&n);    for(int i=1; i<=n; i++)    {        scanf("%d%d",&p[i].s,&p[i].e);    }    sort(p+1,p+n+1);    int e=0,s=0;    int cnt=0;    for(int i=1; i<=n; i++)    {        if(p[i].s>=s)        {            s=p[i].e+1;            cnt++;        }    }    printf("%d\n",cnt);    return 0;}