poj 2573 Bridge （过桥问题贪心）

对于此问题有两种策略

1、最快的带最慢的和次慢的

2、最快和次快带最慢和次慢

<span style="font-size:18px;"><span style="font-size:24px;">#include<stdio.h>
#include<string.h>
#include<algorithm>
#include<iostream>
using namespace std;
int s[1050];
int main()
{
    int a;
    scanf("%d",&a);
    for(int i=0;i<a;i++)
        scanf("%d",&s[i]);
    if(a==1)
    {
        printf("%d\n%d\n",s[0],s[0]);
        return 0;
    }
    sort(s,s+a);
    int ans=a,cne,sum=0,d,e;
    while(ans>3)
    {
        int sum1=2*s[0]+s[ans-2]+s[ans-1];
        int sum2=2*s[1]+s[0]+s[ans-1];
        if(sum1>sum2)
            sum+=sum2;
        else
            sum+=sum1;
        ans-=2;
    }
    if(ans==3)
        printf("%d\n",sum+=s[0]+s[1]+s[2]);
    else
        printf("%d\n",sum+=s[1]);
    while(a>3)
    {
        if(s[0]+s[a-2]<2*s[1])
            printf("%d %d\n%d\n%d %d\n%d\n",s[0],s[a-1],s[0],s[0],s[a-2],s[0]);
        else
            printf("%d %d\n%d\n%d %d\n%d\n",s[0],s[1],s[0],s[a-2],s[a-1],s[1]);
        a-=2;
    }
    if(a==3)
        printf("%d %d\n%d\n%d %d\n",s[0],s[2],s[0],s[0],s[1]);
    else
        printf("%d %d\n",s[0],s[1]);
    return 0;
}
</span></span>

时间： 2024-11-05 19:25:46

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