This code takes input from the user for the number of students, then uses a for loop to iterate from 0 to the number of students to take each student's marks as input and add them to a running total sum, which it finally prints out.

1. int main()
int marks
,i,n,sum=0
10
printf("Enter number of students: ")
scanf("%d",&n)
for(i=0
i<n
++i)
printf("Enter marks of student%d: ",i+1)
scanf("%d",&marks
)
i
sum+=marks
printf("Sum= %d",sum)
i
0