Product point between two vectors [closed]

It can only be done with vectors (or formations or arrays ) of the same dimension. Are you okay?

#include<stdio.h>
#include<math.h>

int main(){
  int a[20],b[20],c[20];
  int i,j,na,nb,suma;

  //Lectura de A
  printf("Tamaño del vector A: ");
  scanf("%d",&na);
  printf("Tamaño del vector B: ");
  scanf("%d",&nb);

  //Lectura de elementos de A
  for(i=0;i<na;i++)
  {
    printf("a(%d) = ", i+1);
    scanf("%d",&a[i]);      
  }

  //Lectura de elementos de B
  for(i=0;i<nb;i++)
  {
     printf("b(%d) = ", i+1);
     scanf("%d",&b[i]);         
  }

  //Producto de los vestores    
  suma=0;
  for(i=0;i<na;i++) 
  {
    suma+=a[i]*b[i];    
  }
  c[i]=suma;

  printf("EL resultado es:%d",c[i]);
}