UVa OJ 1442 - Cav

UVa OJ 1442 - Cav

Problem

Link: 1442 - Cav

Solution

Use greedy algorithm to deal with this problem.

Adjust the height of ceiling to fit the requirements.

Here is the code:

#include <iostream>
#include <cstdio>
using namespace std;

const int maxn = 1e6+5;
int cas, n, cnt;
int ceiling[maxn], floor[maxn];

int main() {
ios::sync_with_stdio(false);
cin.tie(0);
//freopen("input.txt" , "r", stdin );
//freopen("output.txt", "w", stdout);
cin >> cas;
while(cas--) {
cnt = 0;
cin >> n;
for (int i = 0; i < n; ++i) cin >> floor[i];
for (int i = 0; i < n; ++i) cin >> ceiling[i];
int tmp = maxn;
for (int i = 0; i < n; ++i) {
tmp = min(tmp, ceiling[i]);
tmp = max(tmp, floor[i]);
ceiling[i] = tmp;
}
tmp = maxn;
for (int i = n-1; i > -1; --i) {
tmp = min(tmp, ceiling[i]);
tmp = max(tmp, floor[i]);
ceiling[i] = tmp;
cnt += ceiling[i] - floor[i];
}
cout << cnt << '\n';
}
return 0;
}