RECT *assignment_055(RECT head, int application){ RECTafter,*before,*assign; assign=malloc(sizeof(RECT)); assign->size=application; assign->next=NULL; if(application>head->size||application<=0){ assign->address=-1; } else{ before=head; after=head->next; while(after->size<application){ before=before->next; after=after->next;} if(after->size==application){ if(after->size==head->size){ maxblocknum--;} before->next=after->next; assign->address=after->address; free(after);} else{ if(after->size==head->size){ maxblocknum--;} after->size=after->size-application; assign->address=after->address; //大于申请空间则截取相应大小分配 after->address=after->address+application; if(tolower(way)=='b'){ before->next=after->next; //若是最佳适应，将截取后剩余结点重新回收到合适位置 back=after; acceptment2_055(head, back);} if(tolower(way)=='f'){ before->next=after->next; back=after; acceptment1_055(head, back);}} if(maxblocknum==0){ before=head; head->size=0; maxblocknum=1; while(before!=NULL){ if(before->size>head->size){ head->size=before->size; maxblocknum=1;} else if(before->size==head->size){ maxblocknum++;} before=before->next;}}} assign1=assign; return assign1;} //首先适应 void acceptment1_055(RECT *head,RECT *back1){ RECT *before,*after; int insert; before=head; after=head->next; insert=0; while(!insert){ //将回收区插入空闲区表 if((after==NULL)||(back1->address<=after->address && back1->address>=before->address)){ before->next=back1; back1->next=after; insert=1;} else{ before=before->next; after=after->next;}} if(back1->address==before->address+before->size){ //与上一块合并 before->size=before->size+back1->size; before->next=back1->next; free(back1); back1=before;} if(after!=NULL &&(after->address==back1->address+back1->size)){ back1->size=back1->size+after->size; back1->next=after->next; free(after);} if(head->size<back1->size){ head->size=back1->size; maxblocknum=1;} else if(head->size==back1->size){ maxblocknum++; } }代码解释