你可来了,那你帮我看下面的代码有什么地方是不对的,应该怎么改正
int start()
{
double p1,p2,p3,p4,p5,p6,p7,T;
//---------------------p1
if(a>a1&&a1>=a2)
{p1=a;}
else
{p1=0;}
//-----------------------p2
if(a<a1&&a1<=a2)
{p2=a1;}
else
{p2=0;}
//--------------------p3
if(a<=a1&&a>a2)
{p3=a;}
else
{p3=0;}
//--------------------p4
if(a>=a1&&a<a2)
{p4=a;}
else
{p4=0;}
//--------------------p5
if(a<=a2&&a1>a2)
{p5=a2;}
else
{p5=0;}
//--------------------p6
if(a>=a2&&a1<a2)
{p6=a2;}
else
{p6=0;}
//-----------------p7
if(a=a1&&a1=a2)
{p7=a;}
else
{p7=0;}
//------------------T
T=p1+p2+p3+p4+p5+p6+p7;
return(0);
}