Can you find it?
Time Limit: 10000/3000 MS (Java/Others) Memory Limit: 32768/10000 K (Java/Others)
Total Submission(s): 8566 Accepted Submission(s): 2237
Problem Description
Give you three sequences of numbers A, B, C, then we give you a number X. Now you need to calculate if you can find the three numbers Ai, Bj, Ck, which satisfy the formula Ai+Bj+Ck = X.
Input
There are many cases. Every data case is described as followed: In the first line there are three integers L, N, M, in the second line there are L integers represent the sequence A, in the third line there are N integers represent the sequences B, in the forth line there are M integers represent the sequence C. In the fifth line there is an integer S represents there are S integers X to be calculated. 1<=L, N, M<=500, 1<=S<=1000. all the integers are 32-integers.
Output
For each case, firstly you have to print the case number as the form "Case d:", then for the S queries, you calculate if the formula can be satisfied or not. If satisfied, you print "YES", otherwise print "NO".
Sample Input
3 3 3
1 2 3
1 2 3
1 2 3
3
1
4
10
Sample Output
Case 1:
NO
YES
NO
思路:二分法,将Ai+Bj的值存入数组sum中,然后用二分法检测(X-sum[i])是否等于Ck
代码:
#include<iostream>
#include<stdio.h>
#include<string.h>
#include<algorithm>
using namespace std;
int a[510],b[510],c[510],sum[260000],k;
int main()
{
int i,j,x,cnt=1,s,l,m,n,flag,tag,left,right,mid;
while(scanf("%d%d%d",&l,&n,&m)!=EOF)
{
for(i=0; i<l; i++)
scanf("%d",&a[i]);
for(i=0; i<n; i++)
scanf("%d",&b[i]);
for(i=0; i<m; i++)
scanf("%d",&c[i]);
k=0;
for(i=0; i<l; i++)
for(j=0; j<n; j++)
sum[k++]=a[i]+b[j];
sort(sum,sum+k);
scanf("%d",&s);
printf("Case %d: ",cnt++);
while(s--)
{
scanf("%d",&x);
flag=0;
for(i=0; i<m; i++)
{
int t=x-c[i];
left=0;
right=k-1;
tag=0;
while(left<=right)
{
mid=(left+right)>>1;
if(sum[mid]>t)
right=mid-1;
else if(sum[mid]<t)
left=mid+1;
else
{
tag=1;
break;
}
}
if(tag)
{
flag=1;
break;
}
}
if(flag==1)
printf("YES ");
else
printf("NO ");
}
}
return 0;
}
#include<stdio.h>
#include<string.h>
#include<algorithm>
using namespace std;
int a[510],b[510],c[510],sum[260000],k;
int main()
{
int i,j,x,cnt=1,s,l,m,n,flag,tag,left,right,mid;
while(scanf("%d%d%d",&l,&n,&m)!=EOF)
{
for(i=0; i<l; i++)
scanf("%d",&a[i]);
for(i=0; i<n; i++)
scanf("%d",&b[i]);
for(i=0; i<m; i++)
scanf("%d",&c[i]);
k=0;
for(i=0; i<l; i++)
for(j=0; j<n; j++)
sum[k++]=a[i]+b[j];
sort(sum,sum+k);
scanf("%d",&s);
printf("Case %d: ",cnt++);
while(s--)
{
scanf("%d",&x);
flag=0;
for(i=0; i<m; i++)
{
int t=x-c[i];
left=0;
right=k-1;
tag=0;
while(left<=right)
{
mid=(left+right)>>1;
if(sum[mid]>t)
right=mid-1;
else if(sum[mid]<t)
left=mid+1;
else
{
tag=1;
break;
}
}
if(tag)
{
flag=1;
break;
}
}
if(flag==1)
printf("YES ");
else
printf("NO ");
}
}
return 0;
}