不知道哪里写错了，救大命uu们

Question

输入一个正整数 repeat (0<repeat<10)，做repeat 次下列运算：
输入一个职工的月薪 salary，输出应交的个人所得税tax(保留2 位小数)。

tax = rate * (salary-850)
当 salary <= 850 时，rate = 0;
当 850 < salary <= 1350 时，rate = 5;
当 1350 < salary <= 2850 时，rate = 10;
当 2850 < salary <= 5850 时，rate = 15;
当 5850 < salary 时，rate = 20;

为什么这个程序我运行出来，答案是错误的，比如我输入两千，可是程序判断我这个两千属于850-1350

#include<stdio.h>
int main()
{
    int repeat,i,salary;
    double tax,r;
    scanf("%d",&repeat);
    for(i=0;i<repeat;i++){
        scanf("%d",&salary);
        if( salary <= 850){
            r=0;
        }else if( 850<salary<=1350 ){
            r=0.05;
        }else if(1350 < salary <= 2850 ){
            r=0.1;
        }else if(2850 < salary <= 5850){
            r=0.15;
        }else{
        
            r=0.2;
    }
        tax = r*(salary-850);
        printf("tax=%.2f\n",tax);
    }
    return 0;
 }

Answer 1

修改成逻辑运算符吧#include <stdio.h>

int main() {
    int repeat, i, salary;
    double tax, r;
    scanf("%d", &repeat);
    for (i = 0; i < repeat; i++) {
        scanf("%d", &salary);
        if (salary <= 850) {
            r = 0;
        } else if (salary > 850 && salary <= 1350) {
            r = 0.05;
        } else if (salary > 1350 && salary <= 2850) {
            r = 0.1;
        } else if (salary > 2850 && salary <= 5850) {
            r = 0.15;
        } else {
            r = 0.2;
        }
        tax = r * (salary - 850);
        printf("tax=%.2f\n", tax);
    }
    return 0;
}