#ifndefRTX_LIB_H_#defineRTX_LIB_H_#include<string.h>#include<stdint.h>#include"stm32h7xx.h"// Memory Pool Header structuretypedefstruct{uint32_t size;// Memory Pool sizeuint32_t used;// Used Memory}mem_head_t;// Memory Block Header structuretypedefstructmem_block_s{structmem_block_s*next;// Next Memory Block in listuint32_t info;// Block Info or max used Memory (in last block)}mem_block_t;// Memory Block Info: Length = <31:2>:'00', Type = <1:0>#defineMB_INFO_LEN_MASK0xFFFFFFFCU// Length mask#defineMB_INFO_TYPE_MASK0x00000003U// Type mask// Memory Head Pointer
__STATIC_INLINE mem_head_t*MemHeadPtr(void*mem){//lint -e{9079} -e{9087} "conversion from pointer to void to pointer to other type" [MISRA Note 6]return((mem_head_t*)mem);}// Memory Block Pointer
__STATIC_INLINE mem_block_t*MemBlockPtr(void*mem,uint32_t offset){uint32_t addr;mem_block_t*ptr;//lint --e{923} --e{9078} "cast between pointer and unsigned int" [MISRA Note 8]
addr =(uint32_t)mem + offset;
ptr =(mem_block_t*)addr;return ptr;}// ==== Library functions ====// Memory Heap Library functionsexternuint32_tosRtxMemoryInit(void*mem,uint32_t size);externvoid*osRtxMemoryAlloc(void*mem,uint32_t size,uint32_t type);externuint32_tosRtxMemoryFree(void*mem,void*block);#endif// RTX_LIB_H_
rtx_memory.c
#include"rtx_lib.h"// ==== Library functions ====/// Initialize Memory Pool with variable block size./// \param[in] mem pointer to memory pool./// \param[in] size size of a memory pool in bytes./// \return 1 - success, 0 - failure.
__WEAK uint32_tosRtxMemoryInit(void*mem,uint32_t size){mem_head_t*head;mem_block_t*ptr;// Check parameters//lint -e{923} "cast from pointer to unsigned int" [MISRA Note 7]if((mem ==NULL)||(((uint32_t)mem &7U)!=0U)||((size &7U)!=0U)||(size <(sizeof(mem_head_t)+(2U*sizeof(mem_block_t))))){//EvrRtxMemoryInit(mem, size, 0U);//lint -e{904} "Return statement before end of function" [MISRA Note 1]return0U;}// Initialize memory pool header
head =MemHeadPtr(mem);
head->size = size;
head->used =sizeof(mem_head_t)+sizeof(mem_block_t);// Initialize first and last block header
ptr =MemBlockPtr(mem,sizeof(mem_head_t));
ptr->next =MemBlockPtr(mem, size -sizeof(mem_block_t));
ptr->next->next =NULL;
ptr->next->info =sizeof(mem_head_t)+sizeof(mem_block_t);
ptr->info =0U;//EvrRtxMemoryInit(mem, size, 1U);return1U;}/// Allocate a memory block from a Memory Pool./// \param[in] mem pointer to memory pool./// \param[in] size size of a memory block in bytes./// \param[in] type memory block type: 0 - generic, 1 - control block/// \return allocated memory block or NULL in case of no memory is available.
__WEAK void*osRtxMemoryAlloc(void*mem,uint32_t size,uint32_t type){mem_block_t*ptr;mem_block_t*p,*p_new;uint32_t block_size;uint32_t hole_size;// Check parametersif((mem ==NULL)||(size ==0U)||((type &~MB_INFO_TYPE_MASK)!=0U)){//EvrRtxMemoryAlloc(mem, size, type, NULL);//lint -e{904} "Return statement before end of function" [MISRA Note 1]returnNULL;}// Add block header to size
block_size = size +sizeof(mem_block_t);// Make sure that block is 8-byte aligned
block_size =(block_size +7U)&~((uint32_t)7U);// Search for hole big enough
p =MemBlockPtr(mem,sizeof(mem_head_t));for(;;){//lint -e{923} -e{9078} "cast from pointer to unsigned int"
hole_size =(uint32_t)p->next -(uint32_t)p;
hole_size -= p->info & MB_INFO_LEN_MASK;if(hole_size >= block_size){// Hole foundbreak;}
p = p->next;if(p->next ==NULL){// Failed (end of list)//EvrRtxMemoryAlloc(mem, size, type, NULL);//lint -e{904} "Return statement before end of function" [MISRA Note 1]returnNULL;}}// Update used memory(MemHeadPtr(mem))->used += block_size;// Update max used memory
p_new =MemBlockPtr(mem,(MemHeadPtr(mem))->size -sizeof(mem_block_t));if(p_new->info <(MemHeadPtr(mem))->used){
p_new->info =(MemHeadPtr(mem))->used;}// Allocate blockif(p->info ==0U){// No block allocated, set info of first element
p->info = block_size | type;
ptr =MemBlockPtr(p,sizeof(mem_block_t));}else{// Insert new element into the list
p_new =MemBlockPtr(p, p->info & MB_INFO_LEN_MASK);
p_new->next = p->next;
p_new->info = block_size | type;
p->next = p_new;
ptr =MemBlockPtr(p_new,sizeof(mem_block_t));}//EvrRtxMemoryAlloc(mem, size, type, ptr);return ptr;}/// Return an allocated memory block back to a Memory Pool./// \param[in] mem pointer to memory pool./// \param[in] block memory block to be returned to the memory pool./// \return 1 - success, 0 - failure.
__WEAK uint32_tosRtxMemoryFree(void*mem,void*block){constmem_block_t*ptr;mem_block_t*p,*p_prev;// Check parametersif((mem ==NULL)||(block ==NULL)){//EvrRtxMemoryFree(mem, block, 0U);//lint -e{904} "Return statement before end of function" [MISRA Note 1]return0U;}// Memory block header
ptr =MemBlockPtr(block,0U);
ptr--;// Search for block header
p_prev =NULL;
p =MemBlockPtr(mem,sizeof(mem_head_t));while(p != ptr){
p_prev = p;
p = p->next;if(p ==NULL){// Not found//EvrRtxMemoryFree(mem, block, 0U);//lint -e{904} "Return statement before end of function" [MISRA Note 1]return0U;}}// Update used memory(MemHeadPtr(mem))->used -= p->info & MB_INFO_LEN_MASK;// Free blockif(p_prev ==NULL){// Release first block, only set info to 0
p->info =0U;}else{// Discard block from chained list
p_prev->next = p->next;}//EvrRtxMemoryFree(mem, block, 1U);return1U;}
问题描述: 代码:
#include<bits/stdc.h>
using namespace std;
int n, m, k, ans, mod 1e9 7;
long long dp[55][2605];
/*dp[i][j]：第i个街道上建j个房屋的总方案数枚举所有的转移，累加到dp[n][k]即总方案数
*/
int main()
{cin >> n &…
