求助：#3和#5过不了

P1478 陶陶摘苹果（升级版）

Xecades @ 2019-02-01 16:32:41

3和#5都WA，求助！！

code:

#include<iostream>
#include<algorithm>
#include<cstdlib>
#include<cstdio>
using namespace std;

int n,s,a,b;
struct stu
{
    int height;
    int need;
} apples[5010];

bool cmp(stu a,stu b)
{
    return a.need<b.need;
}

int main()
{
    int take=0;
    cin>>n>>s>>a>>b;
    for(int i=1; i<=n; i++)
    {
        cin>>apples[i].height>>apples[i].need;
    }

    sort(&apples[0],&apples[n],cmp);

    for(int i=1; i<=n && s>0; i++)
    {
        if(apples[i].height<=a+b)
        {
            take++;
            s-=apples[i].need;
        }
    }
    cout<<take;
    return 0;
}

by 万弘 @ 2019-02-01 16:44:41

for(int i=1; i<=n; i++)
{
    cin>>apples[i].height>>apples[i].need;
}

sort(&apples[0],&apples[n],cmp);/我觉得应该是sort(apples+1,apples+n+1,cmp);

by 万弘 @ 2019-02-01 16:45:17

因为你输入时下标从1开始

by Xecades @ 2019-02-01 16:45:46

@万弘哦谢谢

by Xecades @ 2019-02-01 16:47:27

貌似没有什么用...还多了个RE https://www.luogu.org/recordnew/show/15993857

by 111l @ 2019-02-01 16:47:38

@万弘好像也不对，我试了一下这个代码，样例都没过

by Xecades @ 2019-02-01 16:49:11

如何？

by 万弘 @ 2019-02-01 16:58:50

#include<iostream>
#include<algorithm>
#include<cstdlib>
#include<cstdio>
using namespace std;

int n,s,a,b;
struct stu
{
    int height;
    int need;
} apples[5010];

bool cmp(stu a,stu b)
{
    return a.need<b.need;
}

int main()
{
    int take=0;
    cin>>n>>s>>a>>b;
    for(int i=1; i<=n; i++)
    {
        cin>>apples[i].height>>apples[i].need;
    }

    sort(apples+1,apples+n+1,cmp);

    for(int i=1; i<=n ; i++)
    {
        if(apples[i].height<=a+b&&s>=apples[i].need)//改了这里
        {
            take++;
            s-=apples[i].need;
        }
    }
    cout<<take;
    return 0;
}

by 111l @ 2019-02-01 16:59:27

1.你没有加特判（n=0时）

2.在循环内特判（s-apples[i].need<0）时输出take-1

3.sort改成 sort(apples+1,apples+n+1,cmp)

然后你就能a了

by 111l @ 2019-02-01 17:01:15

#include<iostream>
#include<algorithm>
#include<cstdlib>
#include<cstdio>
using namespace std;
int n,s,a,b;
struct stu{
    int height;
    int need;
} apples[1111111];
bool cmp(stu a,stu b){
    return a.need<b.need;
}
int main(){
    int take=0;
    cin>>n>>s>>a>>b;
    if(n==0){//特判*1 
        puts("0");
        return 0;
    }
    a+=b;
    for(int i=1; i<=n; i++){
        cin>>apples[i].height>>apples[i].need;
    }
    sort(apples+1,apples+n+1,cmp);
    for(int i=1;s>=0;i++){
        if(apples[i].height<=a){
            take++;
            if(s-apples[i].need<0){//特判*2 
                printf("%d",take-1);
                return 0;
            }
            s-=apples[i].need;
        }
    }
    cout<<take;
    return 0;
}

by Xecades @ 2019-02-01 17:01:16

@光头 @万弘感谢各位大佬