及其丑陋的代码，基本想法就是找连续的符号，把对应数字排序。有很多特殊情况要考虑。。。。 import java.util.Arrays; import java.util.Scanner; public class Main {     public static void main(String[] args) {         Scanner in = new Scanner(System.in);         while (in.hasNext()){             int n = in.nextInt();             int nums[] = new int[n];             char op[] = new char[n];             nums[0] = in.nextInt();             for (int i=1; i<n; i++){                 op[i] = in.next().charAt(0);                 nums[i] = in.nextInt();             }             for (int i=1; i<n;){                 if (op[i] == '+') {                     int j = i;                     while (j<n&&op[j]=='+') j++;                     if (j<n&&(op[j]=='*'||op[j]=='/')){                         if (i==1){                             Arrays.sort(nums,i-1,j-1);                         }                         else {                             Arrays.sort(nums,i,j-1);                         }                     }                     else {                         if (i==1){                             Arrays.sort(nums,i-1,j);                         }                         else {                             Arrays.sort(nums,i,j);                         }                     }                     i=j;                 }                 else if (op[i] == '-') {                     int j = i;                     while (j<n&&op[j]=='-') j++;                     if (j<n&&(op[j]=='*'||op[j]=='/')){                         Arrays.sort(nums,i,j-1);                     }                     else {                         Arrays.sort(nums,i,j);                     }                     i=j;                 }                 else if (op[i] == '*'){                     int j=i;                     while (j<n&&op[j]=='*') j++;                     if (op[i-1]=='/'){                         Arrays.sort(nums, i, j);                     }                     else {                         Arrays.sort(nums,i-1,j);                     }                     i=j;                 }                 else if (op[i] == '/'){                     int j=i;                     while (j<n&&op[j]=='/') j++;                     Arrays.sort(nums,i,j);                     i=j;                 }             }             System.out.print(nums[0]);             for (int i=1; i<n; i++){                 System.out.print(" "+op[i]+" "+nums[i]);             }             System.out.print("\n");         }     } }