CF 586B 起点到终点的最短路和次短路之和

# include <iostream>
# include <cstdio>
# include <cstring>
# include <algorithm>
# include <string>
# include <cmath>
# include <queue>
# define LL long long
using namespace std ;

const int INF = 0x3f3f3f3f ;

int a[3][60] ;
int b[60] ;

int main()
{
int n;
while(scanf("%d",&n) != EOF)
{
int i , j ;
int sum = 0 ;
for (i = 0 ; i < 2  ; i++)
for (j = 0 ; j < n-1 ; j++)
scanf("%d" , &a[i][j]) ;
for (i = 0 ; i < n  ; i++)
scanf("%d" , &b[i]) ;
int ans[3] = {INF , INF , INF} ;
for (i = 0 ; i < n-1  ; i++)
{
sum += a[1][i] ;
}
sum += b[0] ;
ans[2] = sum ;
sort(ans , ans+3) ;
for (i = 0 ; i < n-1  ; i++)
{
sum = sum - a[1][i] + a[0][i] ;
sum = sum - b[i] + b[i+1] ;
ans[2] = sum ;
sort(ans , ans+3) ;
}
printf("%d\n" , ans[0] + ans[1]) ;

}
return 0;
}