 # include <stdio.h>
# include <string.h>
int n, h, t;
char str[100005];
  int main()  {
  while(scanf("%d", &n), n) {
 scanf("%s", str);
int sh = 0, h = 0, t = 0, st = 0, L = strlen(str);
for(int i = 0; i < L; i ++) {
if(str[i] == 'H') h ++;
if(str[i] == 'T') t ++;
 }
if( h % 2 || t % 2) {
puts("-1");
continue;
}
for(int i = 0; i < L / 2; i ++) {
if(str[i] == 'H') sh ++;
if(str[i] == 'T') st ++;
}
int head = 0, tail = L / 2;
while(sh != h / 2) {
if(str[head] == 'H') sh --;
if(str[head] == 'T') st --;
if(str[tail] == 'H') sh ++;
if(str[tail] == 'T') st ++;
head ++; tail ++;
}
if(head != 0) printf("2\n%d ", head);
else printf("1\n");
printf("%d\n", tail);
}
 }
|