2012 2012 Multi-University Training Contest 7 Dragon Ball

如此简单的题目，让我们两个一直卡到最后也没搞出来，我的二分写惨了，他的游标也写错了。现在给出比较靠谱的写法，在下一层定位的时候，把上一层和下一层的合并排序后进行处理，当然这样的方法对于离线的非常有效，在线的还必须得二分，当然二分很纠结。

/*
* File:   main.cpp
* Author: hit-acm
*
* Created on 2012年8月14日, 下午1:14
*/

#include <iostream>
#include <cstdio>
#include <cstring>
#include <cmath>
#include <algorithm>
#include <bitset>
using namespace std;
const int MAXM = 105;
const int MAXN = 1010;
const long long INF = 0x7fffffffffffffffLL;
int m, n, x;
long long t1[MAXN];
long long t2[MAXN];

struct Dragon {
long long val;
long long x;
long long dp;

bool operator<(const Dragon & a)const {
return x < a.x;
}
} mat[MAXM][MAXN];

struct sort_index {
int index;
long long x;
bool color;

bool operator<(const sort_index & a)const {
return x < a.x;
}
} temp[2 * MAXN];

long long solve() {
for (int i = 0; i < m; i++) {
sort(mat[i], mat[i] + n);
}
for (int i = 0; i < n; i++) {
mat[0][i].dp = mat[0][i].val + abs(mat[0][i].x - x);
}

for (int i = 1; i < m; i++) {
for (int k = 0; k < n; k++) {
temp[k].x = mat[i - 1][k].x;
temp[k].index = k;
temp[k].color = true;
temp[n + k].x = mat[i][k].x;
temp[n + k].index = k;
temp[n + k].color = false;
}
sort(temp, temp + 2 * n);
long long min_dis = INF;
for (int k = 0; k < 2 * n; k++) {
if (temp[k].color == true) {
min_dis = min(min_dis, mat[i - 1][temp[k].index].dp - temp[k].x);
} else {
t1[temp[k].index] = min_dis;
}
}

min_dis = INF;
for (int k = 2 * n - 1; k >= 0; k--) {
if (temp[k].color == true) {
min_dis = min(min_dis, mat[i - 1][temp[k].index].dp + temp[k].x);
} else {
t2[temp[k].index] = min_dis;
}
}

for (int j = 0; j < n; j++) {
mat[i][j].dp = INF;
if (t1[j] != INF) {
mat[i][j].dp = min(mat[i][j].dp, mat[i][j].x + t1[j]);
}
if (t2[j] != INF) {
mat[i][j].dp = min(mat[i][j].dp, -mat[i][j].x + t2[j]);
}
mat[i][j].dp += mat[i][j].val;
}
}

long long res = mat[m - 1][0].dp;
for (int i = 1; i < n; i++) {
res = min(res, mat[m - 1][i].dp);
}
return res;
}

int main() {
int T;
scanf("%d", &T);
while (T--) {
scanf("%d%d%d", &m, &n, &x);
for (int i = 0; i < m; i++) {
for (int j = 0; j < n; j++) {
scanf("%lld", &mat[i][j].x);
}
}

for (int i = 0; i < m; i++) {
for (int j = 0; j < n; j++) {
scanf("%lld", &mat[i][j].val);
}
}
printf("%lld\n", solve());
}
return 0;
}