UVALive 3983 Robotruck——单调队列优化dp

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注意一下一开始要把原点入队

#include <cstdio>
#include <cstring>
#include <iostream>
#include <algorithm>
#include <cmath>
using namespace std;
const int maxn = 1e5 + 10;
int T, C, n, x[maxn], y[maxn], w[maxn], diso[maxn];
int sumdis[maxn], sumw[maxn];
int que[maxn], dp[maxn];
inline int func(int x) { return dp[x] - sumdis[x+1] + diso[x+1]; }
void solve() {
    scanf("%d%d", &C, &n);
    sumdis[0] = sumw[0] = x[0] = y[0] = 0;
    for (int i = 1; i <= n; i++) {
        scanf("%d%d%d", &x[i], &y[i], &w[i]);
        diso[i] = abs(x[i]) + abs(y[i]);
        sumdis[i] = sumdis[i-1] + abs(x[i]-x[i-1]) + abs(y[i]-y[i-1]);
        sumw[i] = sumw[i-1] + w[i];
    }
    int l = 1, r = 0;
    que[++r] = 0;
    for (int i = 1; i <= n; i++) {
        while (l <= r && sumw[i] - sumw[que[l]] > C) l++;
        if (l > r) dp[i] = 2*diso[i];
        else dp[i] = func(que[l])+diso[i]+sumdis[i];
        while (l <= r && func(i) <= func(que[r])) r--;
        que[++r] = i;
    }
    printf("%d\n", dp[n]);
}
int main() {
    scanf("%d", &T);
    while (T--) {
        solve();
        if (T > 0) printf("\n");
    }
    return 0;
}