UVALive – 4621 Cav 贪心 ＋ 分析「建议收藏」

#include<cstdio>
#include<algorithm>
using namespace std;
const int N = 1000010;
const int INF = 0x3f3f3f3f;
int s[N], p[N], n;

void init() {
    scanf("%d", &n);
    for(int i = 0; i < n; i++) {
        scanf("%d", &p[i]);
    }

    for(int i = 0; i < n; i++) {
        scanf("%d", &s[i]);
    }
}

int solve() {
    int t = INF;
    for(int i = 0; i < n; i++) {
        t = min(t, s[i]);
        t = max(t, p[i]);

        s[i] = t;
    }

    t = INF;
    for(int i = n - 1; i >= 0; i--) {
        t = min(t, s[i]);
        t = max(t, p[i]);

        s[i] = t;
    }

    int ans = 0;
    for(int i = 0; i < n; i++)
        ans += s[i] - p[i];

    return ans;
}

int main() {
    int test;
    scanf("%d", &test);
    while(test--) {
        init();
        printf("%d\n", solve());
    }
    return 0;
}