例如这道题               ex+y                     x<0,y<0
                     z=   ln(x+y)                 1≤x+y〈10
                          log10|x+y|+1               其它情况

#include <math.h>
#include <iostream.h>
void main()
{
    double x,y,a;
    cin>>x>>y;
    if(x<0&&y<0)
        a=pow(2.7323,x+y);
        else if((x+y)<10&&(x+y)>=1)
            a=log(x+y);
        else if((x+y)>=0)
            a=log10(x+y+1);
        else if(x+y<0)
            a=log10(1-x-y);
        cout<<a<<endl;
}

自然对数的n次方用exp函数
http://en.

你图中的ln对应C函数log
http://en.

你图中的log10
http://en.

谢谢大佬