#include <stdio.h>
#include <stdlib.h>

char* int2hex(int n) {
        static char buffer[256];
        snprintf(buffer, sizeof buffer, "0x%x", n);
        return buffer;
}

int main() {
        int values[] = {0x10, 0x20, 0x25,0x30};
        int i;
        for(i=0; i<sizeof values / sizeof *values; i++) {
                int value = values[i];
                printf("El hexadecimal de %d es %s\n",value, int2hex(value) );
        }
        return 0;
}