#include <iostream>
using namespace std;
int f (int x) {
    int ans = 1;
    for (int i = x; i > 0; i--) ans *= i;
    return ans;
}
int C(int a, int b) {
    if(m==0)return 1;
	int mut=1;
	for(int i=n;i>n-m;i--)mut*=i;
	for(int i=m;i>1;i--)mut/=i;
	return mut;
}
int main () {
    string s;
    int sum = 0;
    cin >> s;
    int n = s.length();
    for (int i = 1; i < n; i++) {
        if (s[i] <= s[i - 1]) {
            cout << 0 << endl;
            return 0;
        }
    }
    for (int i = 1; i < n; i++)
        sum += C(26, i);
    for(int i = 0; i < n; i++)
        for (char j = (i = 0 ? 'a' : s[i - 1] + 1); j < s[i]; j++) 
            sum += C('z' - j, n - i - 1);
    cout << ++sum << endl;
    return 0;
}
为何这东西一直都过不了呢，我拿着题解校对了好久，输入ab给我输出个98，求帮忙