用C++实现十进制到十六进制的两种转换方法

using namespace std;

string itos(int n) {

ostringstream o; o << n; return o.str(); }

string ctos(char n) {

ostringstream o; o << n; return o.str(); }

//采用移位运算，每四位转换为一个十六进制数 void invert_1(vector &v1, int n) {

int bytenum = sizeof(int); int m = 0;

for(int i = 2*bytenum-1; i!=-1; --i) { m = n;

m = (m >> i*4) & ~(~0 << 4);

if(m>=0 && m<=9) v1.push_back(itos(m)); else

v1.push_back(ctos(char(m+55))); } }

//用16去除输入的十进制数

void invert_2(vector &v2, int n) {

int shang = 0; //商 int yushu = 0; //余数 int value = 1; //权值

while(value <= n) {

value = value * 16; yushu = n % value; shang = yushu * 16 / value;

if(shang>=0 && shang<=9) v2.push_back(itos(shang)); else

v2.push_back(ctos(char(shang+55))); }

reverse(v2.begin(),v2.end()); //将向量中的元素倒置 }

void print(vector &v) {

bool first = true; //判断0要不要输出 cout << \"the result is: \";

for(vector::size_type it = 0; it != v.size(); ++it) {

if(v[it]==\"0\" && first == true) continue; else

first = false;

if(first == false) cout << v[it]; }

cout << endl; }

int main() {

vector v1; vector v2;

int input = 0;

cout << \"please input a decimal data: \"; cin >> input;

invert_1(v1,input); invert_2(v2,input);

print(v1); print(v2);

return 0; }