十进制转二进制（最简代码）

#include"iostream"
#include"stdio.h"
using namespace std;

string dui[8]={"000","001","010","011","100","101","110","111"};

int main()
{   
    char ai[100]; int a=125; string jj;
    sprintf(ai,"%o",a);
    for(int i=0;ai[i];i++) jj+=dui[ai[i]-'0'];
    cout<return 0;
}

思路：先将十进制转化为八进制并存储在字符串中，然后八进制以一位对三位转化为二进制