操作系统的编程作业，思路完全按照书上对银行家算法的描述，编译能够通过，但运行时会出错，得不到正确的结果。
我也是受同学所托，希望蝈蝈们能帮我看一下，快崩溃了
估计是那个find函数有点问题，即安全性算法的第二步：从进程集合中找到一个能满足条件Finish【i】=false;Need[i,j]<=Work[j];的进程，找到返回1，否则返回0；

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#include <stdio.h>
#define TRUE 1
#define FALSE 0

int available[256], work[256], finish[256];
int max[256][256], allocation[256][256], need[256][256];

int i, j, temp;

int find(int i, int j)
{
  int row, n, count;

  for (row = 0; row < i; row++) {
    count = 0;
    if (finish[row] == FALSE) {
        for (n = 0; n < j; n++)
          if (need[row][n] <= work[n])
            count++;
          else
            break;
    }
    if (count == j) {
        temp = row;
        return 1;
    }        
  }
  return 0;
}

void security(int id)
{
  int n, cnt;

  for (n = 0; n < j; n++) {
    work[n] = available[n];
  }
  for (n = 0; n < i; n++) {
    finish[n] = FALSE;
  }
  while (find(i, j) == 1) {
    for (n = 0; n < j; n++) {
        work[n] += allocation[temp][n];
    }
    finish[temp] = TRUE;
  }
  for(n = 0; n < i; n++)
    if (finish[n] == TRUE)
        cnt++;
  //printf("\n%d", cnt);
  if (cnt == i)
    printf("\nSystem can allocate the resource to the process P%d.\nIt's safe!\n", id);
  else
    printf("\nSystem can NOT allocate the resource to the process P%d.\nIt's NOT safe!\n", id);
 
}

void banker(int *request, int id)
{
  int n = 0;

  while (n < j) {
    if (request[n] <= need[id][n])
        n++;
    else {
        printf("\nP%d is asking for more resorces than it needs!\n", id);
        return;
    }
  }
  n = 0;
  while (n < j) {
    if (request[n] <= available[n])
        n++;
    else {
        printf("\nP%d is asking for more resorces than it can get!\n", id);
        return;
    }
  }
  for (n = 0; n < j; n++) {
    available[n] -= request[n];
    allocation[id][n] += request[n];
    need[id][n] -= request[n];
  }
  security(id);
}

main()
{
  int n, n1, n2, id, request[256];

  printf("please input the number of process: i = ");
  scanf("%d", &i);
  printf("\nplease input the number of resource: j = ");
  scanf("%d", &j);
  printf("\nplease input the array of Available[]:\n");
  for (n = 0; n < j; n++)
    scanf("%d", &available[n]);
  printf("\nplease input the array Max[][]:\n");
  for (n1 = 0; n1 < i; n1++)
    for (n2 = 0; n2 < j; n2++)
        scanf("%d", &max[n1][n2]);
  printf("\nplease input the array Allocation[][]:\n");
  for (n1 = 0; n1 < i; n1++)
    for (n2 = 0; n2 < j; n2++)
        scanf("%d", &allocation[n1][n2]);
  //the array need[][]
  for (n1 = 0; n1 < i; n1++)
    for (n2 = 0; n2 < j; n2++)
        need[n1][n2] = max[n1][n2] - allocation[n1][n2];
  printf("\nplease input the ID of process which is asking for resource: id = ");
  scanf("%d", &id);
  printf("\nplease input the array of Request[]:\n");
  for (n = 0; n < j; n++)
    scanf("%d", &request[n]);
  banker(request, id);
}

[ 此贴被康师傅在2007-06-18 18:27重新编辑 ]

一步一步的跟踪调试……