int型转二进制,八进制,十六进制查表法

#include <stdio.h>

void toBinary(int num);
void toOct(int num);
void toHex(int num);
void total(int num, int base, int offset);
void toBinary2(int num);
void toOct2(int num);
void toHex2(int num);

int main(int argc, const char * argv[])
{
    toBinary(12);
    toOct(12);
    toHex(12);
    toBinary2(12);
    toOct2(12);
    toHex2(12);
    return 0;
}

void toBinary2(int num){
    total(num, 1, 1);
}

void toOct2(int num){
    total(num, 7, 3);
}

void toHex2(int num){
    total(num, 15, 4);

}

void total(int num, int base, int offset)
{
    char cs[16] = {
        '0','1','2','3','4','5','6','7','8','9','a','b','c','d','e','f'
    };
    char rs[32];
    int len = sizeof(rs) / sizeof(char);
    int pos = len;
    
    while (num) {
        int result = num & base;
        rs[--pos] = cs[result];
        num = num>>offset;
    }
    
    for (int i = pos; i<len; i++) {
        printf("%c", rs[i]);
    }
    
    printf("
");
}

// 转二进制
void toBinary(int num)
{
    char cs[2] = {'0','1'};
    char rs[32];
    int len = sizeof(rs) / sizeof(char);
    int pos = len; // 32
    
    while (num != 0) {
        int result = num & 1;
        rs[--pos] = cs[result];
        num = num>>1;
    }
    
    for (int i = pos; i<len; i++) {
        printf("%c", rs[i]);
    }
    printf("
");
    
}

// 转八进制
void toOct(int num)
{
    char cs[8] = {
        '0','1','2','3','4','5','6','7'
    };
    
    char rs[11];
    int len = sizeof(rs) / sizeof(char);
    int pos = len; // 11;
    
    while (num != 0) {
        int result = num & 7;
        rs[--pos] = cs[result];
        num = num>>3;
    }
    
    for (int i = pos; i<len; i++) {
        printf("%c", rs[i]);
    }
    
    printf("
");
}

// 转十六进制
void toHex(int num)
{
    char cs[16] = {
        '0','1','2','3','4','5','6','7','8','9','a','b','c','d','e','f'
    };
    char rs[8];
    int len = sizeof(rs) / sizeof(char);
    int pos = len;
    
    while (num != 0) {
        int result = num & 15;
        rs[--pos] = cs[result];
        num = num>>4;
    }
    
    for (int i = pos; i<len; i++) {
        printf("%c", rs[i]);
    }
    
    printf("
");
}