NOJ 2143 洗碗

水题 贪心

#include <cstdio>#include <iostream>#include <cstring>#include <string>#include <cmath>#include <algorithm>#include <vector>#include <queue>#include <stack>#include <map>#define inf 1e8using namespace std;typedef long long ll;int n,k;struct note{    int p;    int d;    int sum;};note a[200005];int cmp(note a,note b){    return a.sum>b.sum;}int main(){    scanf("%d%d",&n,&k);    int i;    for(i=0;i<n;i++)    {        scanf("%d%d",&a[i].p,&a[i].d);    }    for(i=0;i<n;i++)    {        a[i].sum=a[i].p+a[i].d;    }    sort(a,a+n,cmp);    ll ans=0;    for(i=0;i<k;i++)    {        ans+=a[i].p;    }    for(;i<n;i++)    {        ans-=a[i].d;    }    if(ans<0)    {        ans=0;    }    cout<<ans<<endl;    return 0;}