Card Shuffle (c++)

#include <iostream>
#include <time.h>
using namespace std;
struct card{
        char color;
        int point;

};

        void shuffle (struct card *deck, int n){
                srand((unsigned) time (NULL));
                        struct card tmp;
                for(int i=0; i< n; i++){
                        int j = rand()%52;
                        tmp = deck[i];
                        deck[i] = deck[j];
                        deck[j] = tmp;

                }

        }
int main(void){
        struct card deck[52];
        for(int i=0; i< 52; i++){
                if(i%4==0){
                        deck[i].color = 's';
                        deck[i].point = (i/4)+1;
                }else if(i%4==1){
                        deck[i].color = 'd';
                        deck[i].point = ((i-1)/4)+1;
                }else if(i%4==2){
                        deck[i].color = 'c';
                        deck[i].point = ((i-2)/4)+1;
                }else{
                        deck[i].color = 'h';
                        deck[i].point = ((i-3)/4)+1;
                }
        }
        shuffle(deck, 52);
        return 0;
}