UVA-11997 K Smallest Sums

UVA - 11997 K Smallest Sums Time Limit: 1000MS   Memory Limit: Unknown   64bit IO Format: %lld & %llu [Submit]   [Go Back]   [Status] Description Problem K K Smallest Sums You're given k arrays, each array has k integers. There are kk ways to pick exactly one element in each array and calculate the sum of the integers. Your task is to find the k smallest sums among them. Input There will be several test cases. The first line of each case contains an integer k (2<=k<=750). Each of the following k lines contains k positive integers in each array. Each of these integers does not exceed 1,000,000. The input is terminated by end-of-file (EOF). The size of input file does not exceed 5MB. Output For each test case, print the k smallest sums, in ascending order. Sample Input 3 1 8 5 9 2 5 10 7 6 2 1 1 1 2 Output for the Sample Input 9 10 12 2 2 Rujia Liu's Present 3: A Data Structure Contest Celebrating the 100th Anniversary of Tsinghua University Special Thanks: Yiming Li Note: Please make sure to test your program with the gift I/O files before submitting! [Submit]   [Go Back]   [Status]

 #include <iostream>
 #include <cstring>
 #include <cstdio>
 #include <queue>
 #include <algorithm>

 using namespace std;

 int arr[][],k;

 struct Item
 {
     int s,b;
     Item() {}
     Item(int x,int y):s(x),b(y){}
     bool operator<(const Item& res) const
     {
         return s>res.s;
     }
 };

 void merge(int *A,int *B,int *C,int n)
 {
     priority_queue<Item> q;
     for(int i=;i<n;i++) q.push(Item(A[i]+B[],));
     for(int i=;i<n;i++)
     {
         Item tmp=q.top();  q.pop();
         C[i]=tmp.s;
         if(tmp.b+<n)
         {
             tmp.s=tmp.s-B[tmp.b]+B[tmp.b+];
             tmp.b++;
             q.push(tmp);
         }
     }
 }

 int main()
 {
     while(scanf("%d",&k)!=EOF)
     {
         for(int i=;i<k;i++)
         {
             for(int j=;j<k;j++)
                 scanf("%d",&arr[i][j]);
             sort(arr[i],arr[i]+k);
         }
         int A[],B[],C[];
         memcpy(A,arr[],sizeof(A));
         for(int i=;i<k;i++)
         {
             memcpy(B,arr[i],sizeof(B));
             merge(A,B,C,k);
             memcpy(A,C,sizeof(A));
         }
         for(int i=;i<k;i++)
         {
             if(i) putchar(' ');
             printf("%d",C[i]);
         }
         putchar();
     }
     return ;
 }