[求助]能看看这段程序哪错了吗_C语言

[求助]能看看这段程序哪错了吗

#include <stdio.h>

void InputData(void);
float CalcNetProfit(void);
void PrnOutput(float);

char sSalesperson[10];
float fTotalSales;
float fCostOfSales;

main()
{ float fNetProfit;

InputData();
fNetProfit=CalcNetProfit();
PrnOutput(fNetProfit);
return 0;
}
void InputData(void)
{
Printf("Enter your name: ");
scanf (" %s",sSalesperson);
printf("Enter your Total Sales: ");
scanf (" %f",&fTotalSales);
printf("Enter your Cost Of Sales: ");
scanf (" %f",&fCostOfSales);
return;
}
float CalcNetProfit(void)
{
float fNetProfit;
fNetProfit=fTotalSales-fCostOfSales;
return fNetProfit;
}
void PrnOutput(float fNetProfit)
{
printf("\n\nAuthor SALES REPORT 02/02/07");
printf("\nSalesperson: %-10s",sSalesperson );
printf("\nTotal : %9.2f",fTotalSales );
printf("\nCost Of Sales: %6.2f",fCostOfSales);
printf("\nNet Profit : %6.2f",fNetProfit);

return;
}

找了一晚上了，没找出哪的错来，刚学C语言，希望能指教一下。
提示是undefined symbol '_printf' in moudule NONAME.C
谢谢了

搜索更多相关的解决方案: include return Enter

----------------解决方案--------------------------------------------------------

#include <stdio.h>

void InputData(void);
float CalcNetProfit(void);
void PrnOutput(float);

char sSalesperson[10];
float fTotalSales;
float fCostOfSales;

main() 改为int main(void)
{ float fNetProfit;

InputData();
fNetProfit=CalcNetProfit();
PrnOutput(fNetProfit);
return 0;
}
void InputData(void)
{
Printf("Enter your name: ");应该为printf
scanf (" %s",sSalesperson);
printf("Enter your Total Sales: ");
scanf (" %f",&fTotalSales);
printf("Enter your Cost Of Sales: ");
scanf (" %f",&fCostOfSales);
return;
}
float CalcNetProfit(void)
{
float fNetProfit;
fNetProfit=fTotalSales-fCostOfSales;
return fNetProfit;
}
void PrnOutput(float fNetProfit)
{
printf("\n\nAuthor SALES REPORT 02/02/07");
printf("\nSalesperson: %-10s",sSalesperson );
printf("\nTotal : %9.2f",fTotalSales );
printf("\nCost Of Sales: %6.2f",fCostOfSales);
printf("\nNet Profit : %6.2f",fNetProfit);

return;
}

----------------解决方案--------------------------------------------------------
谢谢huawang99兄~
问题解决了，是由于第一个printf大写了第一个字母，确实犯了个低级错误。
谢谢你的指正。
----------------解决方案--------------------------------------------------------

都是高手呀！

----------------解决方案--------------------------------------------------------