QQ.c

#include "stdio.h"
#include "string.h"
int main(){
    char a[1000];
    while(fgets(a,1000,stdin)!=NULL){
        int space=0;
        int letter =0;
        if(a[0]==' ')
            space--;
        for(int i=0;i<strlen(a);i++){
            if(a[i]==' '){
                space++;
            }else{
                letter++;
            }
        }
        double output = (double)(letter-1)/(space+1);
        printf("Average word length: %.1f\n",output);
    }
    return 0;
}