please suggest me solution

[Ashutosh1234]

I am trying to multiply 2 matrix of 6x6. But in Result i am getting 00000.....

#include <iostream>
#include<windows.h>
#include <cmath>
#include <string>

using namespace std;
int main()
{
float  x1, x2, x3, y1, y2, y3, y4; 
float  a1, a2, a3, b1, b2, b3, c1, c2, c3;
float area, l1, l2, l3, si1, si2, si3, fi1, fi2, fi3, fi4, fi5, fi6;

float d[6][6];

float m[6][6];

float k[6][6]= {{1,0,0,-1,0,-1},{0,1,0,-1,-1,0},{0,0,1,0,-1,-1},{0,0,0,0,0,0},{0,0,0,0,0,0},{0,0,0,0,0,0}}; 

float s[6][6]={{1,0,0,0,0,0},{0,1,0,0,0,0},{0,0,1,0,0,0},{-1,-1,0,0,0,0},{0,-1,-1,0,0,0},{-1,0,-1,0,0,0}};
cout<<"Value of Mass Matrix :"<<"\n\n";
 for(int i=0; i<=5; i++){
        for(int j=0; j<=5; j++){
          for(int p=0; p<=5; p++){
          d[i][j]=0;
          d[i][j]=(k[i][p]*s[p][j])+d[i][j];
          }}}  
             
cout<<"Mass Matrix =:"<<"\n";                
{for(int i=0;i<=5;i++)
 for(int j=0;j<=5;j++){
cout<<"\t\t"<<d[i][j];
}cout<<"\n";}
return0;
}

[MikeyBoy]

I recommend stepping through the code with a debugger. You'll be able to see the state of all your variables at every step. This should help you see why you're getting the results you're seeing.

[andywestken]

Does line 24 make sense?

Andy

[Ashutosh1234]

what data type should i use

if i delete line 24 output is different.

[ats15]

Move line 24 before line 23

[Ashutosh1234]

which data type should i use for matrix multiplication. I want to minimize digits after decimal.

[nvrmnd]

since you want decimal, you use float and you can use
std::setprecision() if you want to set the width of the decimals to be displayed.

you need to #include <iomanip>