factory.cpp

//Milk Factory
//By: Max Yang
//Time: 45 minutes

#include <stdio.h>
#include <cstdlib>

int main(){
        FILE * In = fopen("factory.in", "r");
        int N;
        fscanf(In, "%d", &N);
        int A[N], B[N];
        for(int i=0; i<=N; i++){
                fscanf(In, "%d %d", &A[i], &B[i]);
        }
        fclose(In);

        for(int i_lines = 1; i_lines <=N-1; i_lines++){
                int lines = i_lines;
                for(int i_stations=1; i_stations<=N; i_stations++){
                        int stations = i_stations;
                        int count;
                        count++;
                        if(B[lines] == stations){
                                break;
                        }
                }
        }
        for(int i_afterlines=1+count; i_afterlines<=N-1; i_afterlines++)
                int afterlines=i_afterlines;
                if(B[afterlines] ==stations){
                        int secound_count;
                        second_count++;
                }
        }

        if(second_count==N-1){
                printf("station: %d", secound_count);
        }else{
                second_count = -1;
        }

        FILE * Out = fopen("factory.out", "w");
        fprintf(Out, "%d\n", second_count);
        fclose(Out);