#include <stdio.h>

int moji(char *A){//
	int i=0,s,count,min=101;
	while(A[s] != '\0'){
		count=0;
		if(A[s]=='c'){i=s;
		while(A[i]!='\0'){
			if(A[i]=='w')count++;
			if(count==2){
				if(min>(i-s+1))min=i-s+1;
				break;}
			i++;
		}
		}s++;
	}
	if(min!=101)return min;
	else return -1;
}
int main(){
	char textA[100000]="";
	scanf("%s",textA);
	printf("\n%d",moji(textA));

}