#include <stdio.h>

int main(){
    int a, b, c, d, e, f, g, h, i, j;
 scanf("%d%d%d%d%d%d%d%d%d", &a, &b, &c, &d, &e, &f, &g, &h, &i);
     if (a == 2) printf("%d\n", 1);
     else if (b == 3) printf("%d\n", 2);
     else if (c == 4) printf("%d\n", 3);
     else if (d == 5) printf("%d\n", 4); 
     else if (e == 6) printf("%d\n", 5);
     else if (f == 7) printf("%d\n", 6);
     else if (g == 8) printf("%d\n", 7);   
     else if (h == 9) printf("%d\n", 8);
     else if (i == 10) printf("%d\n", 9);
     else printf("%d\n", 10);   
     return 0;
}