Convert Decimal Number to Binary or Hex Without itoa function

#include <stdio.h>
#include <stdint.h>

void print_base(uint16_t num, uint8_t base) {
    // Your logic here
    if(base==2){
        int nz,p;
        nz=0;
        for(int i=15;i>=0;i--){
            p=((num>>i)&1);
            if(p!=0){nz=1;}
            if(nz==1){printf("%d",p);}
        }
        if(nz==0){printf("0");}
    }
    else{ int p=0;
        for(int i=0;i<4;i++){
            p|=(num>>4*(3-i));
            p=p&0x0F;
            char hexd=(p<10)?('0'+p):('A'+p-10);
            if (hexd!='0'){printf("%c",hexd);}
            
    }}
}

int main() {
    uint16_t num;
    uint8_t base;
    scanf("%hu %hhu", &num, &base);

    print_base(num, base);
    return 0;
}