C++14(g++5.4) 解法, 执行用时: 380ms, 内存消耗: 16384K, 提交时间: 2018-10-12 20:34:11

#include<bits/stdc++.h>
using namespace std;
#define ll long long
ll a[1005][1005];
ll b[1005],c[1005];
int main(){
	int n,m,k;
	scanf("%d%d%d",&n,&m,&k);
	int z=k/m;
	int d=k%m;
	ll o=0;
	priority_queue<ll> q1[1005];
	for(int i=0;i<n;i++){
		for(int j=0;j<m;j++){
			scanf("%lld",&a[i][j]);
			b[i]+=a[i][j];
			o+=a[i][j];
			q1[i].push(a[i][j]);
		}
	}
	for(int i=0;i<n;i++){
		for(int j=0;j<d;j++){
			c[i]+=q1[i].top();
			q1[i].pop();
		}
	}
	ll ans=1e18;
	for(int i=0;i<n;i++){
		ll s=0;
		s+=c[i];
		priority_queue<ll,vector<ll>,greater<ll> > q;
		for(int j=0;j<n;j++){
			if(i==j)
				continue;
			q.push(b[j]);
		}
		for(int j=0;j<z;j++){
			if(q.size()==0)
				break;
			s+=q.top();
			q.pop();
		}
		ans=min(ans,s);
	}
	if(k==n*m)
		printf("%lld\n",o);
	else
		printf("%lld\n",ans);
}

C++11(clang++ 3.9) 解法, 执行用时: 811ms, 内存消耗: 8416K, 提交时间: 2018-10-12 19:16:36

#include<bits/stdc++.h>
#define ll long long
using namespace std;
int m,n,a[1010],k;
ll s[1010],q[1010],b[1010][1010],ansn=1e18;
int main(){
	cin>>n>>m>>k;
	for (int i=1;i<=n;i++){
		for (int j=1;j<=m;j++)cin>>a[j];
		sort(a+1,a+m+1);
		for (int j=1;j<=m;j++) b[i][j]=b[i][j-1]+a[m-j+1];
		s[i]=b[i][m];
	}
	sort(s+1,s+n+1);
	for (int i=1;i<=n;i++) q[i]=q[i-1]+s[i];
	int x,y;
	if (k%m==0)x=k/m-1;else x=k/m;
	y=k-x*m;
	for (int i=1;i<=n;i++){
		if (b[i][m]<=s[x]){
			ansn=min(ansn,q[x+1]-b[i][m]+b[i][y]);
		}else{
			ansn=min(ansn,b[i][y]+q[x]);
		}
	}
	cout<<ansn<<endl;
	return 0;
}