C++ 代码

#include <iostream>
using namespace std;

int main()
{
    string s,s1,s2;
    int n,m,loc1=-1,loc2=-1;
    char c;
    while(cin>>c,c!=',')    s+=c;
    while(cin>>c,c!=',')    s1+=c;
    while(cin>>c)    s2+=c;
    n = s1.size();
    m = s2.size();

    for(int i=0;i<s.size();i++)
    {
        string sub = s.substr(i,n);
        if(sub == s1)
        {
            loc1 = i;
            break;
        }
    }
    //cout << loc1<<endl;
    for(int j=s.size()-m;j>0;j--)
    {
        string sub = s.substr(j,m);
        if(sub == s2)
        {
            loc2 = j;
            break;
        }
    }
    //cout << loc2<<endl;
    int ans = loc2-loc1-n;
    if(loc1 == -1 || loc2 == -1 || ans < 0 )    cout << -1 <<endl;
    else cout << ans <<endl;


    return 0;
}