CodeForces 522A 手速题

 //戳这里：522A

#include "iostream"
#include "cstdio"
#include "cstring"
#include "algorithm"
#include "map"
using namespace std;
int n;
map<string, int> dp;
void stdstr(string &str)
{
    int len = str.size(), i;
    for(i = 0; i < len; ++i)
        if(str[i] >= 'A' && str[i] <= 'Z')
            str[i] += 32;
}

int main()
{
    int i;
    scanf("%d", &n);
    string n1, str, n2;
    int res = 0;
    for(i = 1; i <= n; ++i) {
        cin >> n1 >> str >> n2;
        stdstr(n1);
        stdstr(n2);
        dp[n1] = dp[n2] + 1;
        res = max(res, dp[n1]);
    }
    printf("%d
", res + 1);
}