1 files changed, 29 insertions, 0 deletions
diff --git a/straight_line_loan.c b/straight_line_loan.c
new file mode 100644
index 0000000..0d25247
--- /dev/null
+++ b/straight_line_loan.c
@@ -0,0 +1,29 @@
+#include "loans.h"
+
+contract *sl_init(int n, int d, float r, float P) {
+	if ((n < 0)) return NULL;
+	if ((d > n)||(d < 0)) return NULL;
+	contract *c = (contract *)calloc(1, sizeof(contract));
+	c->n = (unsigned int)n;
+	c->d = (unsigned int)d;
+	c->r = r;
+	c->P = P;
+	c->D = P/(float)n;
+
+	return c;
+}
+
+float sl_update(contract *c) {
+	if (c->k > c->n)
+		return 0.0f;
+	c->k++;
+	c->I = c->r * c->P;
+	c->P = c->P - c->D;
+	c->A = c->D + c->I;
+
+	return c->A;
+}
+
+void sl_free(contract *c) {
+	free(c);
+}