include

include

include

include

include

include

include

int main(){

int i,len,counto,counts,total;
char* S = (char *)malloc(10240 * sizeof(char));
scanf("%s",S);
len=strlen(S);
len=len/3;
counto=0;
counts=0;
total=0;
for(i=0;i<len;i++) {
    if(S[3*i]!='S') {
        counts++;
    }
    if(S[2*i+2+i]!='S') {
        counts++;
    }
    if(S[3*i+1]!='O') {
        counto++;
    }
}
total=counts+counto;

printf("%d",total);

return 0;

}