急急急，C++ 输入一个奖金数，求税率、应交税款及实得奖金数

奖金税率如下：（a代表奖金，r代表税率） a<100(元) r=0% 100≤a<200 r=2% 200≤a<400 r=4% 400≤a<800 r=8% a≥800 r=10%

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#include <stdio.h>
#define RANK_MAX 4
double rate[RANK_MAX+1] = {0.0, 0.02, 0.04, 0.08, 0.10};
double rank[RANK_MAX] = {100, 200, 400 ,800};
void TaxCalculating(double bonus)
{
int i, j;
double pay = 0, rest = 0;

if( bonus<0 )
{
printf("数据错误.\n");
return;
}

for( i=0; i<RANK_MAX; i++ )
{
if( bonus<=rank[i] )
break;
}

pay = bonus * rate[i];
pay = pay - rank[0]*rate[i];
for( j=1; j<i; j++ )
{
pay -= (rank[j] - rank[j-1]) * (rate[i] - rate[j]);
}

rest = bonus - pay; printf("奖金数：%.2f\n税率：%.2f\n应缴税款：%.2f\n实得奖金：%.2f\n", bonus, rate[i], pay, rest );
return;}
void main()
{
char ans;
double bonus;

do
{
printf("请输入奖金数:");
scanf("%lf", &bonus);
fflush(stdin);
TaxCalculating(bonus);

printf("Go on?(y or Y)?\n");
scanf("%c", &ans);
fflush(stdin);;
} while ( ans=='y' || ans=='Y');

return;}

if (a>=100 && a <200) { cout<<"税率r=2%"<<endl; cout<<"应交税款 = "<<a*0.2<<endl; cout<<"实得奖金数"<<a*0.98<<endl; } 依次这样判断...

#include &lt;stdio.h&gt; #define rank_max 4 double rate[rank_max+1] = {0.0, 0.02, 0.04, 0.08, 0.10}; double rank[rank_max] = {100, 200, 400 ,800}; void taxcalculating(double bonus) { int i, j; double pay = 0, rest = 0; if( bonus&lt;0 ) { printf("数据错误.\n"); return; } for( i=0; i&lt;rank_max; i++ ) { if( bonus&lt;=rank[i] ) break; } pay = bonus * rate[i]; pay = pay - rank[0]*rate[i]; for( j=1; j&lt;i; j++ ) { pay -= (rank[j] - rank[j-1]) * (rate[i] - rate[j]); } rest = bonus - pay; printf("奖金数：%.2f\n税率：%.2f\n应缴税款：%.2f\n实得奖金：%.2f\n", bonus, rate[i], pay, rest ); return;} void main() { char ans; double bonus; do { printf("请输入奖金数:"); scanf("%lf", &amp;bonus); fflush(stdin); taxcalculating(bonus); printf("go on?(y or y)?\n"); scanf("%c", &amp;ans); fflush(stdin);; } while ( ans=='y' || ans=='y'); return;}