1009

The program isn't pass, and the result is RE-- run time error.

although it can pass for the example data.

I can't find the error. I felt it waste time to dig it out, and I don't plan to find it out, at least currently.

Why there isn't any prompt int the online judge system? It should be easy to do it!!!

Thought:

       consider 3 lines, start from one position x - w,  x,  x + w, and the continuous same data are [x - w, a], [x, b], [x + w, c].

       then make n = min ((b - x),  (a - (x -w)),  (c - (x + w)))

       so, there are at most 3 results: the 2 edge value3, and mid value ( same and count is n -2) 

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

int len_in = -1;
int len_out = -1;
int width = 0;
int all = 0;
int in[1024][2] = {{0,0}};
int out[1024 * 20][2] = {{0,0}};

//#define DEBUG
#ifdef DEBUG
#define D(...)
//#define D(...) printf(__VA_ARGS__)
#else
#define D(...)
#endif

static void input(int a, int b);
static void process();
static void output();
int abcd;

int main(int ac, char**av)
{
    int a, b;
    while (1)
    {
        scanf("%d", &width);
        if (width == 0)
        {
            printf("0\n");
            break;
        }

        len_in = -1;
        len_out = 0;
        all = 0;
        memset(out, 0, sizeof(out));
        while (scanf("%d %d", &a, &b))
        {
            if (a == 0 && b == 0)
            {
                process();
                output();
                break;
            }
            input(a, b);
        }
    }

    return 0;
}

void input(int a, int b)
{
    len_in++;
    in[len_in][0] = a;
    in[len_in][1] = b;
    all += b;
}

#ifndef MAX
#define MAX(a,b)    ((a) > (b) ? (a) : (b))
#define MIN(a,b)    ((a) < (b) ? (a) : (b))
#endif

int cal_3(int b, int a1, int a2, int a3)
{
    int max, min;
    max = MAX(a1, MAX(a2, a3));
    min = MIN(a1, MIN(a2, a3));

    max = abs(b - max);
    min = abs(b - min);
    return MAX(max, min);
}
int cal_5(int b, int a1, int a2, int a3, int a4, int a5)
{
    int max, min;
    max = MAX(a1, MAX(a2, MAX(a3, MAX(a4, a5))));
    min = MIN(a1, MIN(a2, MIN(a3, MIN(a4, a5))));

    max = abs(b - max);
    min = abs(b - min);
    return MAX(max, min);
}
int cal_8(int b, int a1, int a2, int a3, int a4, int a5, int a6, int a7, int a8)
{
    int max, min;
    max = MAX(a1, MAX(a2, MAX(a3, MAX(a4, MAX(a5, MAX(a6, MAX(a7, a8)))))));
    min = MIN(a1, MIN(a2, MIN(a3, MIN(a4, MIN(a5, MIN(a6, MIN(a7, a8)))))));

    max = abs(b - max);
    min = abs(b - min);
    return MAX(max, min);
}
void addPair(int v, int n)
{
    if (out[len_out][0] == v)
        out[len_out][1] += n;
    else
    {
        len_out++;
        out[len_out][0] = v;
        out[len_out][1] = n;
    }
}

#define POS_MOVE(p, n, nc) \
    n -= nc; \
if (n == 0) \
{ \
    p++; \
    n = in[p][1]; \
}
void process()
{
    int cur_value = 0;
    int cur_num = 0;
    int p1 = 0; // the previous line
    int p2 = 0; // the current line
    int p3 = 0; // the next line
    int n1 = in[p1][1]; // next change in previous line
    int n2 = 0; // next change in current line
    int n3 = 0; // next change in next line

    // calculate p1, p2, p3
    int nu = 0;
    if ((width == 1) || (all < 3 * width))
        return;
    while (1)
    {
        nu += in[p2][1];
        if (nu <= width) // assume it should more than one line
            p2++;
        else
        {
            break;
        }
    }
    n2 = nu - width; 
    nu = 0;
    if (nu <= width * 2)
    {
        while (1)
        {
            nu += in[p3][1];
            if (nu <= width * 2) // assume it should more than 2 lines
                p3++;
            else
            {
                break;
            }
        }
    }
    n3 = nu - width * 2; 

    D("find the p1 (%d, %d), p2 (%d, %d), p3 (%d, %d), \n",
            p1, n1, p2, n2, p3, n3);

    // do with [0, w)
    int t1 = p1, tn1 = n1, t2 = p2, tn2 = n2;
    cur_value = cal_3(in[t1][0], tn1 > 1 ? in[t1][0] : in[t1+1][0],
            in[t2][0], tn2 > 1 ? in[t2][0] : in[t2+1][0]);
    out[0][0] = cur_value;
    cur_num = 0;
    int i = 0;
    while (i < width)
    {
        int nc = MIN(tn1, tn2);
        nc = MIN(nc, width - i);
        // begin
        int v1 = 0, v2 = 0, v3 = 0;
        if (i == 0)
        {
            v1 = cal_3(in[t1][0], tn1 > 1 ? in[t1][0] : in[t1+1][0],
                    in[t2][0], tn2 > 1 ? in[t2][0] : in[t2+1][0]);
        }
        else if (i == width - 1)
        {
            v1 = cal_3(in[t1][0], in[t1][1] > tn1 ? in[t1][0] : in[t1-1][0],
                    in[t2][0], in[t2][1] > tn2 ? in[t2][0] : in[t2-1][0]);
        }
        else
        {
            v1 = cal_5(in[t1][0],
                    in[t1][1] > tn1 ? in[t1][0] : in[t1-1][0], tn1 > 1 ? in[t1][0] : in[t1+1][0],
                    in[t2][0], in[t2][1] > tn2 ? in[t2][0] : in[t2-1][0], tn2 > 1 ? in[t2][0] : in[t2+1][0]);
        }
        addPair(v1, 1);
        // mid
        if (nc > 2)
        {
            v2 = abs(in[t1][0] - in[t2][0]);
            addPair(v2, nc - 2);
        }
        // end
        if (nc >= 2)
        {
            i += (nc - 1);
            if (i == width - 1)
            {
                v3 = abs(in[t1][0] - in[t2][0]);
            }
            else
            {
                v3 = cal_5(in[t1][0],
                        in[t1][0], tn1 > nc ? in[t1][0] : in[t1+1][0],
                        in[t2][0], in[t2][0], tn2 > nc ? in[t2][0] : in[t2+1][0]);
            }
            addPair(v3, 1);
        }
        i++;
        POS_MOVE(t1, tn1, nc);
        POS_MOVE(t2, tn2, nc);
        D("nc %d, next t1 (%d, %d), t2(%d, %d)\n", nc, t1, tn1, t2, tn2);
    }

    // calculate [w, len-w)
    i = 0;
    while (p3 <= len_in)
    {
        int nc = MIN(n1, MIN(n2, n3));
        // begin
        int v1 = 0, v2 = 0, v3 = 0;
        i %= width;
        if (i == 0)
        {
            v1 = cal_5(in[p2][0],
                    in[p1][0],  n1 > 1 ? in[p1][0] : in[p1+1][0],
                    n2 > 1 ? in[p2][0] : in[p2+1][0],
                    in[p3][0],  n3 > 1 ? in[p3][0] : in[p3+1][0]);
        }
        else if (i == (width - 1))
        {
            v1 = cal_5(in[p2][0],
                    in[p1][0],  in[p1][1] > n1 ? in[p1][0] : in[p1-1][0],
                    in[p2][1] > n2 ? in[p2][0] : in[p2-1][0],
                    in[p3][0],  in[p3][1] > n3 ? in[p3][0] : in[p3-1][0]);
        }
        else
        {
            v1 = cal_8(in[p2][0],
                    in[p1][0],  in[p1][1] > n1 ? in[p1][0] : in[p1-1][0], n1 > 1 ? in[p1][0] : in[p1+1][0],
                    in[p2][1] > n2 ? in[p2][0] : in[p2-1][0], n2 > 1 ? in[p2][0] : in[p2+1][0],
                    in[p3][0],  in[p3][1] > n3 ? in[p3][0] : in[p3-1][0], n3 > 1 ? in[p3][0] : in[p3+1][0]);
        }
        addPair(v1, 1);
        // mid
        if (nc > 2)
        {
            int tmp = abs(in[p1][0] - in[p2][0]);
            v2 = abs(in[p3][0] - in[p2][0]);
            v2 = MAX(tmp, v2);
            addPair(v2, nc - 2);
        }
        // end
        if (nc >= 2)
        {
            i += (nc - 1);
            i %= width;
            if (i == 0)
            {
                v3 = cal_5(in[p2][0],
                        in[p1][0],  n1 > nc ? in[p1][0] : in[p1+1][0],
                        n2 > nc ? in[p2][0] : in[p2+1][0],
                        in[p3][0],  n3 > nc ? in[p3][0] : in[p3+1][0]);
            }
            else if (i == (width - 1))
            {
                int tmp = abs(in[p1][0] - in[p2][0]);
                v3 = abs(in[p3][0] - in[p2][0]);
                v3 = MAX(tmp, v3);
            }
            else
            {
                v3 = cal_5(in[p2][0],
                        in[p1][0],  n1 > nc ? in[p1][0] : in[p1+1][0],
                        n2 > nc ? in[p2][0] : in[p2+1][0],
                        in[p3][0],  n3 > nc ? in[p3][0] : in[p3+1][0]);
            }
            addPair(v3, 1);
        }
        i++;

        POS_MOVE(p1, n1, nc);
        POS_MOVE(p2, n2, nc);
        POS_MOVE(p3, n3, nc);
        D("nc %d, next the p1 (%d, %d), p2 (%d, %d), p3 (%d, %d), \n",
                nc, p1, n1, p2, n2, p3, n3);
    }

    // calculate [len - w, len)
    i = 0;
    while (p2 <= len_in)
    {
        int nc = MIN(n1, n2);
        // begin
        int v1 = 0, v2 = 0, v3 = 0;
        if (i == 0)
        {
            v1 = cal_3(in[p2][0],
                    in[p1][0],  n1 > 1 ? in[p1][0] : in[p1+1][0],
                    n2 > 1 ? in[p2][0] : in[p2+1][0]);
        }
        else if (i == (width - 1))
        {
            v1 = cal_3(in[p2][0],
                    in[p1][0],  in[p1][1] > n1 ? in[p1][0] : in[p1-1][0],
                    in[p2][1] > n2 ? in[p2][0] : in[p2-1][0]);
        }
        else
        {
            v1 = cal_5(in[p2][0],
                    in[p1][0],  in[p1][1] > n1 ? in[p1][0] : in[p1-1][0], n1 > 1 ? in[p1][0] : in[p1+1][0],
                    in[p2][1] > n2 ? in[p2][0] : in[p2-1][0], n2 > 1 ? in[p2][0] : in[p2+1][0]);
        }
        addPair(v1, 1);
        // mid
        if (nc > 2)
        {
            v2 = abs(in[p1][0] - in[p2][0]);
            addPair(v2, nc - 2);
        }
        // end
        if (nc >= 2)
        {
            i += (nc - 1);
            if (i == (width - 1))
            {
                v3 = abs(in[p1][0] - in[p2][0]);
            }
            else
            {
                v3 = cal_3(in[p2][0],
                        in[p1][0],  n1 > nc ? in[p1][0] : in[p1+1][0],
                        n2 > nc ? in[p2][0] : in[p2+1][0]);
            }
            addPair(v3, 1);
        }
        i++;
        POS_MOVE(p1, n1, nc);
        POS_MOVE(p2, n2, nc);
        D("nc %d, next the p1 (%d, %d), p2 (%d, %d), p3 (%d, %d), \n",
                nc, p1, n1, p2, n2, p3, n3);
    }
}
void output()
{
    printf("%d\n", width);
    int i = 0;
    for (i = 0; i <= len_out; i++)
    {
        printf("%d %d\n", out[i][0], out[i][1]);
    }
    printf("0 0\n");
}