在挑戰程式設計競賽上做過類似的，二分答案判斷是否合理。

#include <cstdio>
#include <stack>
using namespace std;
typedef long long LL;

const int maxn = 510;
LL a[maxn];
stack <LL> p[maxn];
int m,k;

bool ok(LL ans) {
    int pos=m,t=k;
    while(t--){
        LL cur=ans;
        while(cur>a[pos]){
            cur-=a[pos--];
            if
 
(!pos) return true;
        }
    }
    return !pos;
}

int main() {
    int t; scanf("%d", &t);
    while(t--) {
        scanf("%d%d", &m, &k);
        LL l = 0, r = 6000000000;
        for(int i = 1; i <= m; ++i) scanf("%lld", &a[i]), l = max(l, a[i]);
        LL  mid = (l + r) / 2;
        while
 
(l < r) {
            mid = l + (r - l) / 2;
            if(ok(mid)){
                if(!ok(mid - 1)){--mid; break;}
                else r = mid + 1;
            }
            else l = mid;
        }
        if(ok(l)) mid = l;
        int pos = m;
        for(int i = k; i > 0; --i){
            while
 
(!p[i].empty()) p[i].pop();
            LL t = mid;
            while(t >= a[pos] && pos) {
                t-=a[pos], p[i].push(a[pos--]);
                if(pos < i) break;
            }
        }
        for(int i = 1; i <= k; ++i) {
            while(!p[i].empty()){
                printf("%lld", p[i].top()), p[i].pop();
                if(!p[i].empty()) printf(" ");
            }
            printf(i == k ? "\n" : " / ");
        }
    }
    return 0;
}