Adding "Grading Students" problem's solution from hackerrank

Hackerrank/gradingStudents.c

@@ -0,0 +1,37 @@
+#include<stdio.h>
+#include<stdlib.h>
+
+
+/*   GRADING STUDENTS PROBLEM 
+Sam is a professor at the university and likes to round each student's grades according to these rules:
+
+If the difference between the grade and the next multiple of 5 is less than 3, round grade  up to the next multiple of 5.
+If the value of grade is less than 38, no rounding occurs as the result will still be a failing grade.
+*/
+
+
+int* gradingStudents(int *grades, int size){
+	for(int i=0;i<size;i++){
+		if(grades[i] % 5 > 2 && grades[i] >= 38)
+			grades[i] += (5 - (grades[i] % 5));
+	}
+	return grades;
+}
+
+
+int main(){
+	int i,n;
+	printf("Enter number of students : ");
+	scanf("%d",&n);
+	int *marks = (int*)calloc(n,sizeof(int));
+	printf("Enter grades of students : ");
+	for(i=0;i<n;i++)
+		scanf("%d",&marks[i]);
+
+	int* roundedMarks = gradingStudents(marks,n);
+	printf("Marks of students after grading : ");
+
+	for(i=0;i<n;i++)
+		printf("%d ",roundedMarks[i]);
+	printf("\n");
+}