#include <stdio.h>

#define LENMAX 50
#define SPAZIO 32

void toUpper(char s[]) {
  int i = 0;
  static char diff = 'A' - 'a';
  
  while(1) {
    if (s[i] == '\0') break; 
    if (s[i] >= 'a' && s[i] <= 'z') {
      s[i] = s[i] + diff;
    }
    i++;
  }
}

int main(int argc, char* argv[]) {
  int i, len;
  char s[LENMAX+1], *p;

  if (argc == 1) {
    puts("Devi dare la string da convertire (max 50 caratteri)");
    return 0;
  }
  
  // merge delle varie string di argv[]
  len = 0;
  for (i=1; i<argc; i++) {
    p = argv[i];
    while(1) {
      if (*p == '\0') {
       	s[len] = SPAZIO;
	break;
      }
      s[len] = *p;
      p++;
      len++;
      if(len == LENMAX) break;
    }
    len++;
  }
  s[len] = '\0';
  
  printf("String ricevuta: %s\n", s);

  toUpper(s);

  printf("String convertita: %s\n", s); 
  
  return 0; 
}