题解 | BFS

#include <stdio.h>
#include <ctype.h>

int main() {
    char s[101];
    scanf("%s\n", s);
    int i=0;
    int result=-1;
    while(s[i]!='\0'&&s[i+1]!='\0'&&s[i+2]!='\0'){
        char c1=tolower(s[i]);
        char c2=tolower(s[i+1]);
        char c3=tolower(s[i+2]);
        if(c1=='b'&&c2=='o'&&c3=='b'){
            result=i;
            break;
        }
        i++;
    }
    printf("%d",result);
    return 0;
}