Pipe not sending accurate information - c

Question

I have started using pipe for a basic exercise. From processes A and B we get 2 random numbers. Process C does the sum of these 2 numbers and it prints it.
The problem is that I don't get the correct values from reading. The values that enter in the pipe are not the ones that exit.
What is the problem here?
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/wait.h>
int main(){
int ac[2],bc[2];
int f,g;
if(pipe(ac)<0 || pipe(bc)<0){
perror("Pipe error");
exit(1);
}
f=fork();
if(f<0){
perror("Error fork1");
exit(2);
}
if(f==0){
g=fork();
if(g<0){
perror("Error fork2");
exit(3);
}
if(g==0){
printf("We are in A \n");
int variab=rand()%11+10;
printf("Here we found the number %d\n",variab);
write(ac[1],&variab,sizeof(int));
}
else{
wait(0);
printf("We are in B\n");
int variab2=rand()%6+5;
printf("Here we found the number %d\n",variab2);
write(bc[1],&variab2,sizeof(int));
}
}
else{
wait(0);
printf("We are in C\n");
int suma;
int s1=read(ac[0],&s1,sizeof(int));
printf("S1=%d\n",s1);
int s2=read(bc[0],&s2,sizeof(int));
printf("S2=%d\n",s2);
suma=s1+s2;
printf("Sum is %d\n",suma);
}
close(ac[0]);
close(ac[1]);
close(bc[0]);
close(bc[1]);
return 0;
}

Answer 1

The problem is with the lines
int s1=read(ac[0],&s1,sizeof(int));
...
int s2=read(bc[0],&s2,sizeof(int));
You are overwriting the value you want to get with the amount of bytes received by the read operation.
Make sure not to assign a new value to s1 and s2 by breaking up the line
int s1;
read(ac[0],&s1,sizeof(int));
(and similarly with s2) and it will work.