发布时间 : 星期日 文章操作系统实验—动态分区分配算法更新完毕开始阅读b29c1c63a0116c175e0e4831
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void print2() //打印作业分区 {
int i;
for (i = 0; i printf(\作业分区ID：%d 起止:%d 结束:%d 长度:%d\\n\, i, zuoye[i].start, zuoye[i].end, zuoye[i].length); } int main() { int i, j, t, len, flag, id; int front, middle, behind; int t1, t2; init(); print1(); printf(\输入1装入新作业，输入0回收作业，输入-1结束\\n\); while (scanf(\, &t) != EOF) { if (t == 1) //装入新作业 { printf(\请输入作业的占用空间的长度 \); scanf(\, &len); flag = 0; for (i = 0; i if (kongxian[i].length >= len) //首次适应算法 { flag = 1; break; } } if (!flag) { printf(\内存分配失败\\n\); } else { //将该作业加入作业区里 zuoye[n2].start = kongxian[i].start; zuoye[n2].end = zuoye[n2].start + len; zuoye[n2].length = len; n2++; //作业数加1 if (kongxian[i].length == len) //该分区全部用于分配，删除该空闲分区 { for (j = i; j kongxian[j].start = kongxian[j + 1].start; kongxian[j].end = kongxian[j + 1].end; kongxian[j].length = kongxian[j + 1].length; } n1--; } else//该空闲分区部分用于分配，剩余的留在空闲分区中 { kongxian[i].start += len; kongxian[i].length -= len; } } } elseif (t == 0) { printf(\输入要回收的作业ID \); scanf(\, &id); front = middle = behind = 0; for (i = 0; i if (kongxian[i].start>zuoye[id].end) break; if (kongxian[i].end == zuoye[id].start) //待回收的作业上面有空闲分区 { front = 1; t1 = i; } if (kongxian[i].start == zuoye[id].end) //待回收的作业下面有空闲分区 { behind = 1; t2 = i; } } if (!front&&!behind) //待回收的作业上下均没有空闲分区 { kongxian[n1].start = zuoye[id].start; kongxian[n1].end = zuoye[id].end; kongxian[n1].length = zuoye[id].length; n1++; //空闲分区增加一个 qsort(kongxian, n1, sizeof(structkongxian), cmp1); //插入空闲分区后排序 for (j = id; j zuoye[j].start = zuoye[j + 1].start; zuoye[j].end = zuoye[j + 1].end; zuoye[j].length = zuoye[j + 1].length; } n2--; } if (front &&behind) //待回收的作业上下均有空闲分区 middle = 1; if (front&&!middle) //合并待回收的作业和上面的空闲分区 { kongxian[t1].end += zuoye[id].length; kongxian[t1].length += zuoye[id].length; for (j = id; j zuoye[j].start = zuoye[j + 1].start; zuoye[j].end = zuoye[j + 1].end; zuoye[j].length = zuoye[j + 1].length; } n2--; } if (middle) //合并待回收的作业和上下的空闲分区 { kongxian[t1].end = kongxian[t2].end; kongxian[t1].length +=(zuoye[id].length + kongxian[t2].length); //删除空闲分区t2 for (j = t2; j kongxian[j].start = kongxian[j + 1].start; kongxian[j].end = kongxian[j + 1].end; kongxian[j].length = kongxian[j + 1].length; } n1--; for (j = id; j zuoye[j].start = zuoye[j + 1].start; zuoye[j].end = zuoye[j + 1].end; zuoye[j].length = zuoye[j + 1].length; } n2--; } } if (behind &&!middle) //合并待回收的作业和下面的分区 { kongxian[t2].start -= zuoye[id].length; kongxian[t2].length += zuoye[id].length; for (j = id; j zuoye[j].start = zuoye[j + 1].start; zuoye[j].end = zuoye[j + 1].end; zuoye[j].length = zuoye[j + 1].length; } n2--; } } else { printf(\操作结束\\n\); break; } print1(); print2(); } return 0; 3.程序运行时的初值和运行结果。 初始： 装入实验要求作业一：