Discrete : wip-worktree-statedescrete

1 files changed, 436 insertions, 0 deletions

diff --git a/01-knapsack/ks_dp2.c b/01-knapsack/ks_dp2.c
new file mode 100644
index 0000000..a776f24
--- /dev/null
+++ b/01-knapsack/ks_dp2.c
@@ -0,0 +1,436 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdint.h>
+#include <time.h>
+#include <unistd.h>
+
+enum { UNSORTED = 0, SORT_WR, SORT_VR, SORT_RW, SORT_RV};
+enum { DESC = 0, ASC };
+enum { NO_RELAX = 0, RELAX };
+
+static int debug;
+static int sort;
+static int sort_order;
+static int relax;
+
+typedef struct _Item
+{
+   int i;
+   int v;
+   int w;
+} Item;
+
+typedef struct _SolverData {
+     int v;    /* cumulated value */
+     int w;    /* cumulated weight */
+     float r;  /* relaxed max value */
+     int i;    /* index of the selected item */
+} SolverData;
+
+typedef struct _Solver
+{
+   int k;               /* capacity */
+   int n;               /* items # */
+   int sum_w;           /* sum of weight of all items */
+   Item *items;         /* items */
+   SolverData *column;  /* solver column */
+} Solver;
+
+static int
+item_cmp(const void *p1, const void *p2)
+{
+   int ret;
+   float r1, r2;
+   const Item *i1, *i2;
+
+   i1 = (const Item *) p1;
+   i2 = (const Item *) p2;
+
+   ret = ((sort_order == ASC) ? 1 : -1);
+
+   if (sort == SORT_WR)
+     {
+        if (i1->w > i2->w) return  ret;
+        if (i1->w < i2->w) return -ret;
+     }
+   else if (sort == SORT_VR)
+     {
+        if (i1->v > i2->v) return  ret;
+        if (i1->v < i2->v) return -ret;
+     }
+   else  // SORT_RW | SORT_RV
+     {
+        r1 = i1->v / (float)i1->w;
+        r2 = i2->v / (float)i2->w;
+        if (r1 > r2) return  ret;
+        if (r1 < r2) return -ret;
+     }
+
+   if (sort == SORT_RW)
+     {
+        if (i1->w > i2->w) return  ret;
+        if (i1->w < i2->w) return -ret;
+     }
+   else if (sort == SORT_RV)
+     {
+        if (i1->v > i2->v) return  ret;
+        if (i1->v < i2->v) return -ret;
+     }
+   else  // SORT_WR | SORT_VR
+     {
+        r1 = i1->v / (float)i1->w;
+        r2 = i2->v / (float)i2->w;
+        if (r1 > r2) return  ret;
+        if (r1 < r2) return -ret;
+     }
+
+   return 0;
+}
+
+static void reset_output(char *output, int bits)
+{
+   char *ch;
+   char *end;
+
+   end = output + bits;
+   for (ch = output; ch < end; )
+     {
+        (*ch++) = '0';
+        (*ch++) = ' ';
+     }
+   ch--;
+   *ch = '\0';
+}
+
+static int print(Solver* solver)
+{
+   int ret;
+   int v, w;
+   char *output;
+   const Item *item;
+   const SolverData *data;
+
+   output = calloc((solver->n * 2), sizeof(char));
+   if (!output)
+     {
+        fprintf(stderr, "ERROR: output calloc\n");
+        return EXIT_FAILURE;
+     }
+   reset_output(output, (solver->n * 2));
+
+   data = solver->column + solver->k;
+   printf("%d %d\n", data->v, 0);
+
+   v = 0;
+   w = 0;
+   for (data = solver->column + solver->k; data->i != -1 ; data -= item->w)
+     {
+        item = &solver->items[data->i];
+        output[(item->i) * 2] = '1';
+        if (debug > 1)
+          printf("  from % 6d  - take % 4d (% 4d % 4d)\n",
+                 data->v, item->i, item->v, item->w);
+        v += item->v;
+        w += item->w;
+     }
+   printf("%s\n", output);
+
+   free(output);
+
+   ret = EXIT_SUCCESS;
+   data = solver->column + solver->k;
+   if (v != data->v)
+     {
+        fprintf(stderr, "ERROR: value %d != %d\n", v, data->v);
+        ret = EXIT_FAILURE;
+     }
+   if (w > solver->k)
+     {
+        fprintf(stderr, "ERROR: weight %d > %d\n", w, solver->k);
+        ret = EXIT_FAILURE;
+     }
+
+   return ret;
+
+}
+
+static inline void relax_item(Solver* solver, SolverData* data, int start)
+{
+   int w;
+   int i;
+   const Item *item;
+
+   w = data->w;
+   data->r = data->v;
+   item = &solver->items[start];
+   for (i = start; i < solver->n; i++, item++)
+     {
+        if ((w + item->w) <= solver->k)
+          {
+             w += item->w;
+             data->r += item->v;
+          }
+        else
+          {
+             data->r += (item->v * ((solver->k - w) / (float)item->w));
+             break;
+          }
+     }
+}
+
+static void solve(Solver* solver)
+{
+   int n, k;
+   int v, w;
+   int i, j;
+   int max_c, upper_bound;
+   const Item *item;
+   SolverData *data;
+   const SolverData *up_left;
+
+   unsigned int counter;
+
+   n = solver->n;
+   k = solver->k;
+   max_c = solver->sum_w;
+
+   /* RELAXATION */
+   if (relax == RELAX)
+     {
+        data = solver->column;
+        for (j = 0; j <= k; j++, data++)
+          relax_item(solver, data, 0);
+     }
+
+   if (debug > 2)
+     {
+        printf("\ncurrent V(i,s,W,r)\n");
+     }
+
+   /* SOLVE */
+   counter = 0;
+   item = solver->items;
+   for (i = 0; i < n; i++, item++)
+     {
+        v = item->v;
+        w = item->w;
+        data = NULL;
+        data = solver->column + solver->k;
+        up_left = solver->column + (solver->k - w);
+
+        // this computes the top-left bottom-right diagonal,
+        // values above this don't need to be computed
+        max_c -= w;
+        upper_bound = (((k - max_c) > w) ? (k - max_c) : w );
+        for (j = k; j >= upper_bound; j--, data--, up_left--)
+          {
+             // FIXME
+             /* if ((relax == RELAX) && (data->v == (int)data->r)) */
+             /* if ((relax == RELAX) && (data->v <= (int)data->r)) */
+             /* if ((relax == RELAX) && (data->v < (int)data->r)) */
+             /*   { */
+             /*      /1* fprintf(stderr,"RELAX\n"); *1/ */
+             /*      continue; */
+             /*   } */
+
+             counter++;
+
+             if (data->v < (v + up_left->v))
+               {
+                  data->i = i;
+                  data->v = v + up_left->v;
+                  data->w = w + up_left->w;
+                  /* if (j == k) */
+                  /*   { */
+                  /*      for (critical = data; critical->i != -1 ; */
+                  /*           critical -= solver->items[data->i].w) */
+                  /*        { */
+                  /*           critical->c = critical->i; */
+                  /*        } */
+                  /*      print_vector(solver, i + 1, 0); */
+                  /*      print_vector(solver, i + 1, 1); */
+                  /*   } */
+               }
+
+             /* RELAXTION must be cached */
+             if (relax == RELAX)
+               {
+                  relax_item(solver, data, (i + 1));
+               }
+          }
+
+        if (debug > 2)
+          {
+             printf("i=%d; j=k; j<=%d:\n", i, upper_bound);
+             data = solver->column;
+             for (j = 0; j <= k; j++, data++)
+               printf("  % 4d(% 2d % 2d %.1f)\n",
+                      data->v, data->i, data->w, data->r);
+             printf("\n");
+          }
+     }
+
+   if (debug > 0)
+     printf("loops count: %u\n", counter);
+
+   if (debug == 2)
+     {
+        printf("i=%d:\n", solver->n - 1);
+        data = solver->column;
+        for (j = 0; j <= k; j++, data++)
+          printf("  % 4d(% 2d % 2d %.1f)\n",
+                 data->v, data->i, data->w, data->r);
+     }
+}
+
+int main(int argc, char** argv, char** env)
+{
+   FILE *fp;
+
+   int opt;
+   int ret;
+   int i;
+   uint64_t dt;
+   struct timespec t0;
+   struct timespec t1;
+
+   Solver solver;
+   Item *item;
+
+   sort = UNSORTED;
+   sort_order = DESC;
+   relax = NO_RELAX;
+   debug = 0;
+   while ((opt = getopt(argc, argv, "d:s:SR")) != -1) {
+        switch (opt) {
+           case 's':
+              sort = atoi(optarg);
+              break;
+           case 'd':
+              debug = atoi(optarg);
+              break;
+           case 'S':
+              sort_order = ASC;
+              break;
+           case 'R':
+              relax = RELAX;
+              break;
+           default: /* '?' */
+              fprintf(stderr, "Usage: %s [-d level] [-s 0|1] [-S] [-R]input\n",
+                      argv[0]);
+              return EXIT_FAILURE;
+        }
+   }
+
+   if (sort > SORT_RV) sort = UNSORTED;
+   if (sort_order > ASC) sort = DESC;
+
+   if (optind >= argc) {
+        fprintf(stderr,"input file missing\n");
+        return EXIT_FAILURE;
+   }
+
+   if (debug > 0) printf("%s\n", argv[optind]);
+   fp = fopen(argv[optind], "r");
+   if (fp == NULL)
+     {
+        fprintf(stderr, "I couldn't open results.dat for reading.\n");
+        return EXIT_FAILURE;
+     }
+
+   /* read k and n */
+   if (fscanf(fp, "%d %d\n", &solver.n, &solver.k) != 2)
+     {
+        fprintf(stderr, "ERROR: read first line\n");
+        return EXIT_FAILURE;
+     }
+   if (debug > 0) printf("  K:%d N:%d\n", solver.k, solver.n);
+
+   /* allocate */
+   solver.items = calloc(solver.n, sizeof(Item));
+   if (!solver.items)
+     {
+        fprintf(stderr, "ERROR: items calloc\n");
+        return EXIT_FAILURE;
+     }
+
+   solver.column = calloc((solver.k + 1), sizeof(SolverData));
+   if (!solver.column)
+     {
+        free(solver.items);
+        fprintf(stderr, "ERROR: column calloc\n");
+        return EXIT_FAILURE;
+     }
+   for (i = 0; i < (solver.k + 1); i++)
+     solver.column[i].i = -1;
+
+   /* read items */
+   solver.sum_w = 0;
+   item = solver.items;
+   for (i = 0; i < solver.n; i++, item++)
+     {
+        item->i = i;
+        fscanf(fp, "%d %d\n", &item->v, &item->w);
+        solver.sum_w += item->w;
+     }
+   fclose(fp);
+
+   if (sort != UNSORTED)
+     qsort(solver.items, solver.n, sizeof(Item), item_cmp);
+
+   if (debug > 1)
+     {
+        printf("  Items ");
+        if (sort == UNSORTED)
+          {
+              printf("unsorted\n");
+          }
+        else
+          {
+             printf("sorted ");
+             switch(sort){
+                  case SORT_VR:
+                     printf("Value,ratio(V/W)");
+                     break;
+                  case SORT_WR:
+                     printf("Weight,ratio(V/W)");
+                     break;
+                  case SORT_RW:
+                     printf("ratio(V/W),Weight");
+                     break;
+                  case SORT_RV:
+                     printf("ratio(V/W),Value");
+                     break;
+                  default:
+                     break;
+             }
+            if (sort_order == ASC)
+              printf(" asc\n");
+            else
+              printf(" desc\n");
+          }
+        item = solver.items;
+        printf("     index    Value   Weight\n");
+        for (i = 0; i < solver.n; i++, item++)
+          printf("  % 8d % 8d % 8d\n", item->i, item->v, item->w);
+     }
+
+   clock_gettime(CLOCK_MONOTONIC, &t0);
+   solve(&solver);
+   clock_gettime(CLOCK_MONOTONIC, &t1);
+   ret = print(&solver);
+
+   if (debug > 0)
+     {
+        dt = ((t1.tv_sec * 1000000000) + t1.tv_nsec) -
+           ((t0.tv_sec * 1000000000) + t0.tv_nsec);
+        printf(" time %7u [ms]\n", (unsigned int)(dt/1000000));
+     }
+
+   free(solver.items);
+   free(solver.column);
+
+   return ret;
+}
+