UVa 1422 processors.

#include <stdio.h>
#include <stdlib.h>
#include <limits.h>

#define MAX_N 20001

typedef struct
{
    int begin, end, w;
} Program;

Program program[MAX_N];
int myHeapLength, n;

int cmpV1(Program *a, Program *b)
{
    return a->begin - b->begin;
}

Program myHeap[MAX_N];

void heapPush(Program e)
{

    int i = myHeapLength, p;
    Program t;
    myHeap[myHeapLength++] = e;
    while(i)
    {
        p = (i - 1) / 2;
        if(myHeap[i].end < myHeap[p].end)
        {
            t = myHeap[i];
            myHeap[i] = myHeap[p];
            myHeap[p] = t;
            i = p;
        }
        else
            break;
    }
}

Program heapPop()
{
    int minChild, i = 0;
    Program e = myHeap[0], t;
    myHeap[0] = myHeap[--myHeapLength];
    while((minChild = 2 * i + 1) < myHeapLength)
    {
        if(minChild + 1 < myHeapLength && myHeap[minChild + 1].end < myHeap[minChild].end)
            ++minChild;
        if(myHeap[i].end > myHeap[minChild].end)
        {
            t = myHeap[i];
            myHeap[i] = myHeap[minChild];
            myHeap[minChild] = t;
            i = minChild;
        }
        else
            break;
    }
    return e;
}

int check(int x)
{
    int i = 0, curTime = 0, time;
    Program e;
    myHeapLength = 0;
    while(1)
    {
        if(myHeapLength == 0 && i == n)
            return 1;
        if(myHeapLength == 0 && i < n)
        {
            e = program[i++];
            if(e.end <= curTime)
                return 0;
            if(e.begin > curTime)
                curTime = e.begin;
            heapPush(e);
        }
        else
        {
            ++curTime;
            while(i < n && program[i].begin < curTime)
                heapPush(program[i++]);
            time = x;
            while(time)
            {
                if(myHeapLength)
                {
                    e = heapPop();
                    if(e.end < curTime)
                        return 0;
                    if(e.w > time)
                    {
                        e.w -= time;
                        time = 0;
                        heapPush(e);
                    }
                    else
                    {
                        time -= e.w;
                    }
                }
                else
                    break;
            }
        }
        if(curTime > 20000)
            return 0;
    }

}

int main()
{
    freopen("d:/input.txt", "r", stdin);
    int T, i, min, max, m;
    Program t;
    scanf("%d", &T);
    while(T--)
    {
        scanf("%d", &n);
        for(i = 0; i < n; ++i)
        {
            scanf("%d%d%d", &program[i].begin, &program[i].end, &program[i].w);
        }
        qsort(program, n, sizeof(Program), cmpV1);
        min = 1;
        max = INT_MAX;
        while(min < max)
        {
            m = min + (max - min) / 2;
            if(check(m))
                max = m;
            else
                min = m + 1;
        }
        printf("%d\n", max);
    }
    return 0;
}