lang
1import java.io.BufferedReader; 2import java.io.InputStreamReader; 3import java.util. *;; 4 5public class Main { 6 public static void main(String[] args) throws Exception { 7 BufferedReader bf = new BufferedReader(new InputStreamReader(System.in)); 8 Scanner scan = new Scanner(System.in); 9 int odd = 0; 10 int even = 0; 11 int[] row = new int[15]; 12 13 int n = scan.nextInt(); 14 15 for(int start = 0; start < n; start++){ 16 String line = bf.readLine(); 17 18 for(int i = 0; i < 15; i++){ 19 String a = line.substring(i, i+1); //NullPointerException 20 row[i] = Integer.parseInt(a); 21 } 22 23 for(int eve = 0; eve < 15; eve = eve + 2){ 24 even += row[eve]; 25 } 26 27 even = even * 2; 28 29 for(int od = 1; od < 15; od = od + 2){ 30 even += row[od]; 31 } 32 33 for(int x = 0; x < 10; x++){ 34 if(odd + even + (x + 2) % 10 == 0){ 35 System.out.println(x); 36 break; 37 } 38 } 39 40 } 41 } 42}
といったソースを書きました。
row[i] = Integer.parseInt(a);
のところでNullpointerExceptionとなります。なぜでしょうか?
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