#include<bits/stdc++.h> using namespace std; unsigned int getBlkno(string &input_data,int idx){ string s = input_data.substr(idx*4,4); unsigned int res = 0; for(int i=0;i<4;i++){ res += s[i]<<(24-i*8); } return res; } unsigned int Murmurhash3(string input_data,unsigned int seed){ unsigned int h = seed; //声明常量 const unsigned int c1 = 0xcc9e2d51; // 3,432,918,353 const unsigned int c2 = 0x1b873593; // 461,845,907 const int r1 = 15; const int r2 = 13; const int m = 5; const int n = 0xe6546b64; //3,864,292,196 //分块处理 int blkNums = input_data.size()/4; //1.一个块一个块地处理,这是第一部分地工作 for(int i=0;i<blkNums;i++){ unsigned int K = getBlkno(input_data,i); K *= c1; K = _rotl(K,r1); K *= c2; K = _rotl(K,r2); h = h*m + n; } //2.处理剩余量 string remaining_bytes = input_data.substr(blkNums*4); unsigned int k = 0; switch (remaining_bytes.size()){ case 3:k^=remaining_bytes[2]<<16; case 2:k^=remaining_bytes[1]<<8; case 1:k^=remaining_bytes[0]; } k = k * c1; k = _rotl(k,r1); k = k * c2; h ^= k; h ^= input_data.size(); //3.加强雪崩测试 h ^= h >> 16; h *= 0x85ebca6b; // 2,246,822,507 h ^= h >> 13; h *= 0xc2b2ae35; // 3,266,489,909 h ^= h >> 16; return h; } int main(){ string input_data = "Jack"; int seed = 123; cout<<"Murmurhash3(Jack,123) = "<<Murmurhash3(input_data,seed); system("pause"); }

这是一个C++程序，实现了MurmurHash3哈希算法的功能。该程序定义了两个函数，getBlkno函数用于获取指定字符串块的哈希值，MurmurHash3函数则是主要的哈希函数，用于计算输入字符串的哈希值。在主函数中，程序通过调用MurmurHash3函数计算了字符串"Jack"的哈希值，并输出到控制台。