十六进制转八进制

迈不过友情╰ 2022-06-01 12:59 205阅读 0赞

1.先转化为二进制

#include<iostream>
    using namespace std;  
    int main()   
    {   
    	int n,m,i,j,k;
    	cin>>n;
    	string sixteen[10];
    	for(i=0;i<n;i++){
    		cin>>sixteen[i];
    	}
    	for(i=0;i<n;i++){
    		string tow;
    		string eight;
    		char eig;
    		for(j=0;j<sixteen[i].size();j++){//注意什么时候用单引号什么时候用双引号
    			switch(sixteen[i][j]){
    				case '0':tow+="0000";break;
                    case '1':tow+="0001";break;
                    case '2':tow+="0010";break;
                    case '3':tow+="0011";break;
                    case '4':tow+="0100";break;
                    case '5':tow+="0101";break;
                    case '6':tow+="0110";break;
                    case '7':tow+="0111";break;
                    case '8':tow+="1000";break;
                    case '9':tow+="1001";break;
                    case 'A':tow+="1010";break;
                    case 'B':tow+="1011";break;
                    case 'C':tow+="1100";break;
                    case 'D':tow+="1101";break;
                    case 'E':tow+="1110";break;
                    case 'F':tow+="1111";break;
                    default:break;
    				}
    			}
    			m=tow.size()%3;//用“0”补齐位数（属于字符串所以用双引号）
    			if(m==1)
    			tow.insert(0,"00");
    			else if(m==2)
    			tow.insert(0,"0");
        if(!(tow[0]=='0'&&tow[1]=='0'&&tow[2]=='0'))//很重要，用来去除首位0
                {
                eig=(tow[0]-'0')*4+(tow[1]-'0')*2+(tow[2]);
                eight=eight+eig;
                }
    			for(k=3;k<tow.size();k=k+3){
    				if(tow.substr(k,3)=="000")
    					eight+="0";
    				else if(tow.substr(k,3)=="001")
    					eight+="1";
    				else if(tow.substr(k,3)=="010") 
    					eight+="2";
    				else if(tow.substr(k,3)=="011")
    					eight+="3";
    				else if(tow.substr(k,3)=="100")
    					eight+="4";
    				else if(tow.substr(k,3)=="101")
    					eight+="5";
    				else if(tow.substr(k,3)=="110")
    					eight+="6";
    				else if(tow.substr(k,3)=="111")
    					eight+="7";
    				}
    			cout<<eight<<endl;
    		}
    	return 0;
    }

2.先转为十进制（编译器测试正确然而练习系统给了我0分2333）

#include <stdio.h> 
    #include <string.h>  
    #include <math.h>
    #include<iostream>
    using namespace std;  
    int main()   
    {   
    	int n,j;
    	scanf("%d",&n);
    	long long a[n];
    	string strHex[10];
    	int i, len = 0, temp = 0;  
    	long long nDec = 0;  
    	for(j=0;j<n;j++){	    
    	    cin>>strHex[j];    
    	    for (i = 0; strHex[j][i] != '\0'; i++)  
    	    {  
    	    	len = strHex[j].size();
    	        switch(strHex[j][i])  
    	        {  
    	        case 'A': temp = 10; break;  
    	        case 'B': temp = 11; break;  
    	        case 'C': temp = 12; break;  
    	        case 'D': temp = 13; break;  
    	        case 'E': temp = 14; break;  
    	        case 'F': temp = 15; break;  
    	        default: temp = strHex[j][i]-'0'; break;  
    	        }  
    	        nDec += (temp*pow(16,len-1-i));  
    	    } 
    		a[j]=nDec;
    		nDec=0;		 
    	}
    	for(j=0;j<n;j++){
    		printf("%o\n",a[j]);
    	}
        return 0;
    }