（注：暂时先记录这些问题，后期会持续更新）

1，用函数实现财务现金记账

#include
     
      float cash;  //定义全局变量，保存现金余额int main(void){    int choice;    float value;    void income(float number),expend(float number);  //函数声明        cash = 0;    printf("Enter operte choice(0--end,1--income,2--expend):");    scanf("%d",&choice);  //输入操作类型    while(choice != 0){        if(choice == 1||choice == 2){            printf("Enter cash value:");  //输入操作现金额             scanf("%f",&value);            if(choice == 1)                income(value);  //计算现金收入             else                expend(value);  //计算现金输出            printf("current cash:%.2f\n",cash);         }        printf("Enter operte choice(0--end,1--income,2--expend):");        scanf("%d",&choice);  //继续输入操作类型    }     return 0;} void income(float number){    cash = cash + number;  //改变全局变量cash }void expend(float number){    cash = cash - number;}
     

 

 

2，用函数实现餐厅记账

#include
     
      float total = 0.0;short count = 0;short tax_percent = 6;float add_with_tax(float f)  //返回一小笔金额{    float tax_rate = 1 + tax_percent / 100.0;  //有了.0，计算就会以浮点数进行，否则表达式会返回整数    total = total + (f * tax_rate);    count = count + 1;    return total; } int main(){    float val;    printf("Price of item:");    while(scanf("%f",&val)==1){        printf("Total so far:%.2f\n",add_with_tax(val));        printf("Price of item:");    }    printf("\nFinal total:%.2f\n",total);    printf("Number of items:%hi\n",count);    return 0;}